The higher the RF ride height the tighter the car will be.
The higher the REAR ride heights, the more drag on the straight-away, but the better the rear will stick in the corners.
A higher LF will tighten the chassis.
A higher LR will loosen the chassis.
A higher RR will tighten the chassis.
A higher LR lowers the RF and may cause the RF of the chassis to drag.
With in the garage area of NASCAR Racing we are given the option of keeping track of our adjustments during practice sessions. Due to the importance of good note keeping, I'm going to once again remind everyone the importance of keeping track of various adjustments made throughout practice sessions.
It is critical to take notes after every adjustment you make. With all the adjustments available to make, it's real easy to forget what adjustment you made 3 practice sessions ago. Record keeping is important. If you do go the wrong way with an adjustment you can always set it back to where it was before making the change by simply referring back to your notes. By tracking & logging information, it also allows you to refer back to them to see how you progressed to cure your handling problem. These notes could be useful for setups at tracks with familiar configurations which can turn out to be a real time saver. By keeping track of adjustments, you will be able to refer back to your notes to see what worked & what didn't. This will help you decide what to adjust if a similar situation arises at another track.
Above I've included two setup sheets for taking notes. You could also use the setup notes option within the garage area to track your changes. I personally would rather track notes on paper because they are are easier to refer to when trying to set up a car at another track with a similar configuration. What I do like to keep track of in the setup notes area is what type of tire wear I get with the current setup. Before running an event, I refer to these notes so I know what tire will wear 1st, & when approximately I will have to pit. Fuel mileage is another thing to keep track of. Knowing how many laps you can get on a fuel run will allow you to keep in the back of your mind, when you will be forced to pit. Can I make it on a full tank of fuel or will I need tires first. If so what lap will I have to pit should we go green the whole way.
Top speed & or lap times is also a must to keep track of. I also like to keep track of how the car reacts as tires wear, as well as how it performs with less fuel in the car. How bad do lap times decrease over X number of laps. What chassis adjustments could I make during a pit stop to help counter react the way the chassis performs with less fuel. Perhaps a track bar or tire pressure adjustment would be the way to go when pitting after so many laps. All these types of questions I have answered before entering a race because of good note keeping. Keeping track of these types of notes in the setup notes section of the garage area will allow you to perform better on the track & could even get you a win by knowing how your chassis will react before even turning a lap.
After running so many different tracks & working on so many different setups, it's real easy to forget how one setup reacts over another. Simply reading your setup notes will remind you once again what you can expect from the setup you will be running before even getting on the track. If you have multiple setups for various weather conditions reviewing these notes will allow you to choose what setup to run given the current track conditions. This is where using the track notes section of the garage area comes in handy (read the section on track notes).
Shocks
Shocks are designed to control the up & down movement of the suspension caused by weight transfer as well as bumps. A shock controls the speed at which the spring moves. Without shocks a car would handle like a boat in the water, swaying back & forth while moving up & down. Understanding shocks & how they work will give you a major advantage over those that don't. Controlling the chassis with the proper shocks is the key to getting through a corner smoothly & effortlessly. Shocks are used to help control handling problems & can even be used to induce desirable handling characteristics.
Of all the questions I am asked regarding setup options, shocks are by far the most asked & most misunderstood of all the setup options available to us in NASCAR Racing. Shocks are a very easy issue to become confused about. At times, too much or too little of the same adjustment on the same shock can produce the same exact results in the chassis. (i.e. it's possible to have a push with a RF shock that is both too stiff or too soft). Such results end up in total confusion as which way is the right way to go with an adjustment. The most important thing to remember regarding shocks, is that the stiffer the shock, the less grip it will have at the corner or end of the chassis.
Shocks do NOT control the amount of weight transfer in a corner. They will however control how quickly the weight is transferred. Shocks used on WC teams are rated from 1 through 9. 1 being very soft while 9 being very stiff. We also have the same choice for shock adjustments within NASCAR Racing at all four corners of the car at tracks where NASCAR doesn't mandate specific shock settings. Shocks are numbered for both compression & rebound. The compression of a shock is when it is being pressed down. The rebound is when it is being pulled back up. By adjusting the valving (changing the numbers) within the shock, we are able to change the stiffness or weakness of that shock when it is both compressed & pulled back or rebounded.
When you have a shock that has the same number compression as rebound it is said to be a 50/50 shock. This means that the shock when compressed, has the same resistance when pulled apart. A shock with a compression rating of 9, & a rebound rating of 9, is telling you that the shock is really hard to compress & just as hard to pull back apart or rebound. A shock with a compression rating of 9 & a rebound of 1 is what they call a split valved shock. This shock would be stiff to compress, but would rebound or pull apart real easy. Through adjustment of the shock valves you are able to control how quickly weight is unloaded left to right, & front to rear. By adjusting the valving of each shock you can fine tune your chassis through a corner. Once you understand this concept of how shocks work, you will be able to use that knowledge to turn faster & more consistent laps.
When discussing shock tuning in depth, a basic understanding of dynamic weight transfer and its effect on tire loadings is necessary. Dynamic weight transfer is the transferring of weight from side to side during cornering, from rear to front during deceleration and from front to rear during acceleration. The distribution of weight that transfers is affected by the rates of the springs used in the chassis. Basically, if one of a pair of springs receiving weight is stiffer than the other, the stiff spring receives proportionately more weight than the soft spring. The rate at which a tire is loaded or unloaded during dynamic weight transfer is affected by the compression & rebound of the associated shock. In rebound, a stiff shock slows down and a soft shock speeds up the unloading process. In compression, a stiff shock slows down and a soft shock speeds up the loading process. However, excessively soft or stiff shocks can produce effects opposite to those stated. Consequently, by changing the stiffness of the shocks used on a race car, we are adjusting the loadings on the tires at different points on the race track. If done correctly, good handling will result.
Now that you understand the compression & rebound of a shock, you must learn how & when they are used while cornering. The easiest way for me to explain when a shock is doing it's most work, is by using an ordinary automobile as an example. Imagine a vehicle going down the highway at 50mph. Now imagine this vehicle slamming on it's brakes. What occurs in the chassis? When you slam on the brakes all the weight is transferred to the front of the vehicle & the nose of the car dives while the back of the car raises up. What are the shocks going through in this state? The front shocks are being compressed & the rear shocks are extending or rebounding. Generally speaking, this is the exact same thing that occurs in a racecar upon entering the corner. (minus the locking up of the brakes of course) The shocks are going through the same basic process as the regular street car. Therefore if your having troubles getting into the corner, you would adjust the front shocks compression, & or the rear shocks rebound, since that's the stages of the shocks being utilized upon entry into a corner.
Let's take the same street vehicle & imagine it at a stand still in a parking lot. Giving the car full throttle what occurs? Just the opposite of what was explained above. The front of the car lifts while the rear of the car squats. The shocks up front are rebounding & the rear shocks are compressing. The shocks on a race car are going to react the same way in the middle of a corner when your chassis takes set to full throttle. Therefore if your having problems exiting the corners under acceleration, you would look at adjusting the rebound of the front shocks, & or the compression of the rear shocks.
Keep in mind the above comparisons are being used to help you better understand the basic concepts of shocks & how & when they perform. In reality there is a lot more involved because a racecar enters a corner with a lot more force which varies the degree of each shock & how much they are being compressed or rebounded. Add to the fact that adjustments can be made asymmetrically from left to right & or front to rear, & it opens up all new options & possibilities for additional adjustments that can produce different results.
The balance of traction between the left side and right side tires determines to a great extent how the car will handle while decelerating through the corner. For example, a race car will tend to push whenever the left side tires do not have enough influence in stopping the car (the right side tires are slowing the vehicle more than the left so the vehicle tends to go to the right). By using stiffer shocks (especially a stiffer rebound on the LR & LF), the unloading process of the inside tires (due to dynamic weight transfer) to the outside tires slows. Consequently, the left side tires remain loaded further into the corner which helps to turn the chassis. This should allow a car to drive in deeper & remain more balanced throughout a right-hand turn. Softer left side & or rebound would give just the opposite results.
Asymmetrically changing the front or rear shocks can also give different results on the handling of a chassis. Decreasing the rebound on both front shocks allows the weight to transfer quicker from the front to the rear under acceleration. This will loosen a chassis more as throttle is applied. (remember stiffer means less grip on that end) Therefore with stiffer shocks on the rear, it would mean less grip on the rear tires. Increasing the rebound would produce just the opposite effects. Asymmetrically adjusting the rear shocks will also produce different effects as compared to adjusting individual corners.
Shocks & springs do work alike. If you understand springs (read the spring section) you will have a better understanding of how shocks operate. All of the asymmetrical theories that apply to springs also apply to shocks in much of the same manner. In other words a stiffer RF shock will tighten a chassis much the same as a stiffer RF spring will, albeit to a much lesser degree. A stiffer RR shock & spring will loosen the chassis, etc. etc. Stiffer front springs & shocks will make a car tight. (stiffer in this instance means less grip at the front)
The part that throws people for a loop in regards to shocks, is when after an adjustment is made the results are unseen or not felt in the chassis immediately. To begin with your not always going to feel a major change. Shocks adjustments are a fine tuning device only to be used after the rest of the chassis is close to being neutral or stable. The easiest way to adjust shocks & get a feel for how they work are to adjust them as a 50/50 shock. Or in other words start out adjusting the compression & rebound equally the same. Say 9 compression 9 rebound, or 1 compression 1 rebound. With a 9/9 shock you have a shock as stiff as it gets. A 1/1 is a weak as it gets. Try these settings one at a time at different corners of the car to see the changes & how they affect the handling of the car. A 9/9 on the RF will tighten the chassis all the way through the corner. While a 9/9 on the RR will loosen the chassis all the way through a corner. A 1/1 will have just the opposite effects. Once again I bring up stiffer equals less grip on that corner. Stiffer RF equals push because the RF will have less grip & begin to slide. Stiffer RR & that tire will have less grip & slide which will make you loose.
The reason many drivers do not feel a shock change is because they quickly forget the stiffer shock or shocks produce the least amount of grip. Therefore adjusting your 7/7 RF shock to 6/6 has little influence over your 4/4 rear shocks. The RF is still stiffer. Only once you understand the influence a so called 50/50 shock has on each corner of the car, should you attempt to adjust the split valving of each individual shock. Read the synopsis below for a better understanding of the effects on adjusting the compression & rebound of each individual shock & the effects you may experience with such an adjustment.
Before adjusting shocks, try to visualize how weight is being transferred at each corner upon deceleration, braking, & acceleration. With a better understanding, you will have a much easier time deciding which shock to adjust to help cure or smooth your corner transitioning problem properly.
Proper compression & rebound settings basically come down to what a driver feels more comfortable with. What works with one driver, might not necessarily be correct for another. This is due to the fact that different drivers have different driving techniques. Smooth throttle, brake and steering transitions will require slower shock travel because weight isn't being transferred as quickly compared to those drivers that use abrupt throttle, brake, and steering transitions.
PRELOAD
Preload can come from several sources. Take for example a coil over shock that has a threaded collar for supporting the spring. If the collar has been turned up a number of times so the spring is compressed even when the shock is fully extended then the spring would be preloaded. In other words there is a load on the spring before there is any shock compression. On the whole car, due to spring placement, suspension positioning, and tire diameters, etc., you can have a preloaded affect just like the single coil over unit. Adjustments (in or out) on the weight jack screws is the most common way the preload is changed.
Below is a general guide that should assist you in fine tuning your shocks.
SHOCK COMPRESSION:
The stiffer the FRONT shocks, (higher the number) the tighter the car will be when braking.
The softer the FRONT shocks, (lower the number) the looser the car will be when braking.
The stiffer the REAR shocks, (higher the number) the looser the car will be under acceleration.
The softer the REAR shocks, (lower the number) the tighter the car will be under acceleration.
SHOCK REBOUND:
The stiffer the FRONT shocks, (higher the number) the tighter the car will be under acceleration.
The softer the FRONT shocks, (lower the number) the looser the car will be under acceleration.
The stiffer the REAR shocks, (higher the number) the looser the car will be under braking.
The softer the REAR shocks, (lower the number) the tighter the car will be under braking.
Shock synopsis:
RF
Higher compression will tighten the chassis entering a corner.
Lower compression will loosen the chassis entering a corner.
Higher rebound will tighten the chassis accelerating out of a corner.
Lower rebound will loosen the chassis accelerating out of a corner.
Overall stiffer RF shock will tighten chassis, weaker will loosen it.
RR
Higher compression will loosen the chassis accelerating out of a corner.
Lower compression will tighten the chassis accelerating out of a corner.
Higher rebound will loosen the chassis entering a corner.
Lower rebound will tighten the chassis entering a corner.
Overall stiffer RR shock will loosen chassis, weaker will tighten it.
LF
Higher compression will tighten the chassis entering a corner.
Lower compression will loosen the chassis entering a corner.
Higher rebound will tighten the chassis accelerating out of a corner.
Lower rebound will loosen the chassis accelerating out of a corner.
Overall stiffer LF shock will loosen chassis, weaker will tighten it.
LR
Higher compression will loosen the chassis accelerating out of a corner.
Lower compression will tighten the chassis accelerating out of a corner.
Higher rebound will loosen the chassis entering a corner.
Lower rebound will tighten the chassis entering a corner.
Overall stiffer LR shock will tighten chassis, weaker will loosen it.
Asymmetrical changes:
The stiffer the shock, the less grip that tire will have.
Stiffer rebound on the left shocks will help the car turn in by slowing weight transfer to the right.
Stiffer compression on the right shocks will help the car turn in by also slowing weight transfer to the right.
Softer rebound on the front shocks will loosen the chassis exiting the corner.
Softer compression on the rear shocks will tighten the chassis exiting the corner.
Doing just the opposite mentioned above, on either compression or rebound will produce just the opposite results.
Asymmetrical changes seem to have a greater influence than individual shock changes.
General:
Use the above info as a guideline only. Changing just one shock may not give you the exact results mentioned above. Other factors must be considered. Other shocks & settings as well as asymmetrical changes will produce different results with varying degrees of chassis changes or feelings based on other components & driving style.
Spoiler
Your spoiler adjustment is another option that is located under the drivetrain/aero tab within the garage menu. The spoiler itself is a wide piece of rigid aluminum located on the rear deck lid that spans the length of the trunk. The purpose of a spoiler is to add down force to the rear of the car. This is accomplished by how the air is passed over the back of the trunk lid as it hits the spoiler.
The same basic theories that apply to an airplane wing apply to a spoiler on a race car. When an airplane takes off from a runway, you'll notice that the rear flaps on the wings point downward. This is actually just the opposite of how a spoiler works on a WC race car. When the flaps are pointed down on an airplane it assists the plane is lifting up to get off the ground. This isn't an effect you would want in a race car. On a WC car the spoiler is in just the opposite position catching air & adding down force to the rear of the chassis. This is the effect we desire at most race tracks. The rear spoiler catches air pushing down on the back of the car allowing for better traction through the corners.
How much air catches the spoiler is determined by what angle the spoiler is placed at and the rake of the chassis based on ride height. NASCAR Racing allows us a range of adjustment from as low as 45 degrees, to as high as 70 degrees. The lower the number the straighter the spoiler or the less down force there will be on the rear of the car. The higher the number the higher the angle of the spoiler & the more down force there will be applied to the back of the car. Note: On restrictor plate tracks like Daytona and Talladega, NASCAR mandates the spoiler be set at 55 degrees and thus is non adjustable.
You may think a setting of 70 would be the best for cornering, and it might very well be depending on the track. The disadvantage to running a higher spoiler angle is that it increases drag slowing you down on a straightaway. Picture yourself holding your hand out the window of an automobile traveling 55 mph, with your palm facing down towards the road. You'll notice how the wind pushes your hand back a little bit. This would be similar to a spoiler angle of 45 degrees in a race car. Now take your hand & rotate it 90 degrees so your palm is facing the front of the vehicle. You'll notice how much stronger the wind appears to be pushing your hand when you rotate it. This would be similar to you running an angle of 70 degrees on your rear spoiler. Obviously the force on a rear spoiler going 180 mph over the length of the rear deck lid will be a lot higher than your hand out a window. But you get the idea of how wind, aerodynamics, & spoilers effect the performance of a race car.
On a high banked high speed track like Talladega, you'll probably want to run the minimum spoiler angle since down force isn't as critical. A track like Talladega naturally creates down force on the car. The majority of other tracks will require higher degrees of spoiler to keep the rear end glued to the track. To keep it simple, the higher the spoiler angle the tighter the rear will be. The lower the angle the looser the rear will be.
Spoiler synopsis:
The higher the angle the slower your straight-away speeds.
The lower the angle the faster your straight-away speeds.
The lower the angle the looser the chassis.
The higher the angle the tighter the chassis.
Springs
Four coil springs are located at each corner of the chassis. The springs determine how much weight is transferred to each corner of the car. The springs are mounted in such a way that they can be adjusted up or down to change ride heights. Springs are rated by how many pounds it takes to compress the spring 1". This is done using a special tool called a spring compressor.
The ideal spring combination is one that would produce equal amounts of wheel travel at all four corners of the car. At all ovals, the heaviest weight is being transferred towards the RF upon entry into a corner. This means the RF corner of the car will travel more requiring a stiffer spring than the other 3 corners. The higher the numbers the stiffer the spring. In NASCAR Racing we are allowed spring adjustments at all 4 corners of the chassis. (excluding Daytona and Talladega) The front springs allow us an adjustment as low as 450 lbs. & as high as 2500 lbs. The front springs are adjustable in 50 lb. increments. The rear springs can be adjusted as low as 150 lbs. & as high as 700 lbs. in increments of 25 lbs.
An overall softer spring package is usually preferred over a stiffer setup. With a softer setup though, you run the risk of having the car bottom out on the track. This can be cured by using a stiffer sway bar & or raising ride heights. Using softer springs will cause the car to roll over more in the corners. This may require using higher camber angles to compensate for the roll.
In general stiffer front springs will make the car tighter. Stiffer rear springs will loosen the car. Weaker front & rear springs will have just the opposite effect. By changing the spring stagger between the LF & RF as well as the LR & RR, you are able to effect the way the car reacts under acceleration & braking. Spring stagger is the difference in spring rating between the left & right side of the chassis. Running more spring stagger up front, with a weaker left side spring, will tighten the car under acceleration while loosening it under braking. i.e. a 800 LF spring & a 1000 RF spring. The greater the difference, the greater the chassis response during these transitions. Running more spring stagger in the rear, with a weaker left side spring, will have just the opposite effect as the front. Instead of tightening the car, it will loosen the car under acceleration & tighten it while braking.
The RF & RR springs change the roll couple distribution of the chassis. A stiffer RF spring will make the car tighter. This is because the the stiffer corner won't accept the body roll & will continue forward creating a push. A stiffer RR spring will have just the opposite effect & create a loose condition. The LF & LR springs effect the chassis by changing the wedge or cross weight in the car. A stiffer LF spring will make a car looser going in & coming out of a turn because it takes wedge out of the car. A stiffer LR spring will tighten the car from the middle, out of a corner because it keeps cross weight in the car.
You'll notice that when making a spring change either stiffer or weaker, it will have the same effect on the chassis as it's diagonal opposite corner. In other words, if you decide to make the RF spring weaker to help loosen the car, you could also make the diagonal opposite corner (LR) weaker to also help loosen the car. In all actuality, what your doing by changing both diagonal corners together, is changing the wedge or cross weight of the chassis. Try to remember the diagonal corners as pairs. And that whatever one pair does, the opposite pair will have the opposite effect. Using this method makes remembering what spring does what a little easier. In reality then, all you have to remember is what one spring adjustment does, and you should remember how all the others corners are effected.
Let me give you an example. Just remember that a stiffer RF spring equals a tighter condition. Now I know that diagonally a stiffer LR spring also equals a tighter condition. Now a stiffer RR & LF (diagonally) would have just the opposite effect (loose) on the chassis. Now if I have a loose race car, I now know I can try a stiffer RF or LR spring, or a weaker RR or LF spring. All will help to tighten the chassis. I remember all this by simply knowing that a stiffer RF spring equals a tighter race car.
As you can see, it's really easy to get confused over what spring does what & how their strength or weakness effect a chassis while cornering. Let's try to put it in it's simplest form.
Spring synopsis:
Weaker LF will make the car tight.
Weaker RR will make the car tight.
Weaker RF will make the car loose.
Weaker LR will make the car loose.
Stiffer RF will make the car tight.
Stiffer LR will make the car tight.
Stiffer LF will make the car loose.
Stiffer RR will make the car loose.
Overall stiffer front springs will make the car tight.
Overall stiffer back springs will make the car loose.
Overall weaker front springs will make the car loose.
Overall weaker back springs will make the car tight.
Increasing front spring stagger will tighten the car under acceleration & loosen it under braking.
Increasing rear spring stagger will loosen the car under acceleration & tighten it under braking. (This will become more apparent as the RF tire wears and may cause the chassis to snap lose in the latter stages of a tire/fuel run)
Steering Ratio
Steering ratio is the difference in how many degrees your front wheels are turned compared to how many degrees your steering wheel is turned. Steering ratio is measured by dividing the number of degrees the tire is turned into the number of degrees the steering wheel is turned. If for example you turn your steering wheel 180 degrees & your front tires were to turn 10 degrees you would have a 18:1 steering ratio. (10 into 180 = 18)
Your steering ratio adjustments range from 12:1 to 32:1 within NASCAR Racing. The lower the ratio (12:1) the quicker the steering response. You'll notice that using a lower steering ratio will require less turning of the wheel to negotiate a corner. This low steering ratio can result in a twitchy car since the smallest of steering inputs will be felt in the car. It is very easy to over steer a car with such a low steering ratio.
A car with a higher steering ratio (32:1) will require more steering input to get through a corner. Too high a steering ratio might give the feeling of a tight race car as you find yourself turning the wheel further to negotiate a turn. This isn't a push, it's just requiring more movement in the wheel to steer the front tires the same amount as with a lower ratio. With a ratio of 12:1 at a track like Michigan you might only have to turn the steering wheel 45 degrees to the left to get through the corner. With the same exact setup, but a ratio of 32:1 you might have to turn the wheel 90 degrees or more to the left to negotiate the same exact corner.
There is no correct setting for steering ratio. It all depends on the driver & what he is comfortable with. A lot of this depends on the type of steering device used. With so many different wheels on the market, you wont know what is comfortable for you until you experiment with it yourself. You may be comfortable with a steering ratio of 24:1 at Dover with a TSW brand wheel, but find that after using a MadCatz wheel that the ratio is all wrong. This is because some wheels turn more or less degrees than others requiring different steering ratio settings.
As a general rule of thumb, the smaller the track & tighter the radius of the turn, the lower the ratio you'll want to run. Road courses are a track with slow sharp turns that would require a lower ratio. High speed long sweeping corners would not require such a low steering ratio since you are not required to turn as sharply on tracks like these.
Steering Ratio synopsis:
The lower the ratio the quicker the steering response.
The higher the ratio the slower the steering response.
Lower ratios require less turning of the wheel to negotiate a corner.
Higher ratios require more turning of the wheel to negotiate a corner.
Tire Pressure
Tires are the most important component on a race car. You can have the fastest engine
or the best possible setup, but if you don't have a set of tires between you & the track, everything else is meaningless. In fact, every single thing you adjust on a race car is for the benefit of the tires. All these adjustments that I've discussed in this guide are all about trying to achieve the best possible grip from the tires to the track. If you have the best grip at all 4 wheels, then you'll have the fastest car on the track.
Tire pressure is yet another adjustment that will aid you in achieving the best possible grip. Tire pressure is simply how much air you have in a tire. The hotter tires get, the more they expand. Air contains moisture. Moisture becomes steam as the air gets hot & increases pressure. WC teams actually don't use air in their tires they use nitrogen. Nitrogen is preferred over air because it doesn't expand as much with temperature changes because it doesn't contain moisture. Since it's impossible to remove all the moisture from a tire, it will still change pressure as temperatures rises. This can be noted after running a test session & checking your tires both hot & cold. When tires expand it changes the size of the tire which in turn changes the weight on that wheel. This can be either a negative or positive situation depending on your chassis needs.
Tire pressures can be adjusted on all 4 tires from as low as 8 psi. to as high as 60 psi. Improper tire pressure can cause an ill handling car. Correct tire pressure can be determined by reading tire temperatures. A tire with a temperature reading higher in the center of a tire indicates an over inflated tire. A tire with a lower center temperature, when compared to the inside & outside of a tire indicates a under inflated tire. Over inflated tires will have a tendency to make the car tight. Under inflation can slightly loosen a chassis but give better grip. Lower tire pressure will also increase the amount of heat in that tire. Excessively low tire pressure produces more heat which can result in quicker wear. Higher pressure tires run cooler, have less drag & will be quicker at higher speeds.
Stagger isn't a direct adjustment we can make in NASCAR Racing. NASCAR regulates the size of their tires which come with stagger already built into the tire. Altering tire pressures allows us to slightly modify the stagger. Stagger is the circumference of the right side tires compared to the left side tires. The best way I can describe stagger is by using a white Styrofoam coffee cup. You know, the kind that is bigger around on the top than on the bottom. Take that cup & lay it over on it's side on a table. Now push it along the table letting it roll. You see how it turns in one direction. This is stagger. Imagine the top or larger side of the cup as the right side tires on a race car. Imagine the bottom or smaller side of the cup as the left side tires. See how it turns left? Stagger on a race car works the same exact way. By increasing tire pressure on the right side, or decreasing pressure on the left we add stagger to the chassis allowing the car to turn left better through a corner especially under acceleration.
One thing to keep in mind when dealing with tire pressures, is that your also changing the weight of the car on the corner your lowering or raising pressure at. By raising or lowering pressure your changing the ride height of the chassis. Changing the ride height adds or subtracts weight from that corner of the chassis. So tire pressure actually reacts like a spring. Adding more tire pressure makes that corner of the chassis a little stiffer. Lowering tire pressure will tend to make that corner of the car softer.
Tire psi synopsis:
Higher psi in RF will loosen the car.
Lower psi in the RF will tighten the car.
Higher psi in RR will loosen the car.
Lower psi in the RR will tighten the car.
Higher psi in the LR will tighten the car from the middle out.
Lower psi in the LR will loosen the car from the middle out.
Higher psi in the LF will tighten the car.
Lower psi in the LF will loosen the car.
The lower the psi in a tire the hotter it will run.
The higher the psi in a tire the colder it will run.
Excessively low front tire psi will create a push.
Excessively low rear tire psi will create a loose condition.
Increasing the split (more RR psi than LR) increases stagger, helping the car to turn in the middle of a corner.
Increasing the split of the left & right side psi (more psi on the right) increases the pull to the left.
Tire pressure allows us to fine tune the chassis. Drastic pressures changes at various corners of the chassis could produce less than desirable results. Keep an eye on tire temperatures. Although your changing the weight on each tire with tire pressure, your changing it to a much lesser degree than with a spring change. If you know & understand how springs work, you'll be that much further ahead when understanding how tire pressure changes effect the chassis.
Tire Temperatures
When I talk about the inside of each tire, I'm referring to the edge closest to the brake rotors or inside of the car. When I refer to the outside edge of each tire, I'm referring to those edges that are furthest from the brake rotors. Tires are marked within NASCAR Racing as O for outside, M for middle, & I for inside. See the accompanying photo for a better understanding of the outside & inside of each tire.
I previously mentioned that every adjustment we attempt to make on a racecar, is an attempt to try an maximize the grip of each tire. By taking tire temperatures of each tire we can "read" how well our chassis is performing. A good tire man can tell how a racecar is handling without ever watching it perform on the track & without even talking to the driver. Tire temperatures are the only scientific proof we have of how a chassis is working. It's easy for a driver to misinterpret how a car is handling. Tire temperatures eliminate that mystery by telling us which corner of the car is over or under worked.
The information I am going to discuss below, is what I've learned over the years working on real race cars. Some of the tire testing information I will mention below has given me various results within the sim. Some of this information transfers over to the sim rather well. Use this information to the best of your advantage to better understand the concept behind reading tire temperatures.
Tire temperatures are taken with a tool called a tire pyrometer. This tool is inserted into the tire on the inside, middle, & outside of each tire to give us readings across the surface of the tire. By comparing tire temperatures across the surface of the front tires we are able to tell if we have proper camber angles, proper toe, proper weight distribution, as well as proper tire inflation. By reading the average temperature of the RF & comparing it to the average temperature of the RR we can tell if the chassis is loose or tight. Comparing diagonal averages indicate the proper amount of wedge in the chassis.
The optimal tire temperatures should be in a range of 190 to 240 degrees. Keep in mind that the hotter the tire the quicker it will wear out. It's important to realize what the outside & inside of each tire is. The inside of each tire is the edge closest to the brake rotors or inside of the car. The outside edge of each tire are those edges that are furthest from the brake rotors. See photo above for outside & inside edges of tire temperatures.
On a short track it is normal for the outside edge of the RF tire & the inside edge of the LF to be 5 to 10 degrees cooler. This is because of the way the tires travel down the straightaway. On a larger track with longer straights, this spread will be even further. On an oval, the RF tire will have more negative camber, thus resulting in the inside edge of the tire contacting the track more than the outside edge giving you the higher temperature. On the LF you will run with more positive camber, so just the opposite holds true. While cornering these temperatures should even out if you have the correct amounts of camber & or weight transfer. The more camber you run, the higher these spreads will be. On a small track were you spend a lot of time cornering, you'll find the spread not as high. This is because your spending more time cornering than on the straights, thus distributing the temperatures across the face of the tire more evenly. If you try to achieve even temps across the tire you may develop a push. This is telling you that you have too much positive camber. Although the tire may be flat on the track, on a straightaway, the tire will not be flat on the track while cornering.
By comparing the average temperature of all four tires you can see which corner of the chassis is working harder than the other. To figure the average temperature of a tire, add the 3 temps across the tire & divide by three. If your RF is a lot hotter than the other three tires your probably pushing because the RF is doing too much work. Work on cooling that tire off by lowering the RF spring and allowing the other tires to share some of the work load. By comparing the RF average to the RR average you can tell if the chassis is loose or tight. The RF should be about 10 degrees hotter than the RR. If it's higher your probably pushing. If it's lower your loose. A tire is being under worked when it's temperature is a lot lower than the other three tires. When a tire is cooler or under worked, try concentrating on that corner of the car. Try adding weight to that corner of the car to increase the temperature of that tire. If a tire is a lot hotter than the other 3 work on making that tire cooler.
It's also informative to compare right & left side, front & rear, as well as diagonal averages. Print & use the tire temperature sheet I've provided to help track all this information. To see if you have the proper wedge, average the RF & LR tires & compare them to the two front averages & two right side averages. Your diagonal average should be 5 to 10 degrees cooler than both the front & right side averages. If it is warmer you have too much cross weight. If it's cooler then you need more cross weight or wedge.
The best way to decipher tire temperatures is to run 10 laps on a particular setup & monitor tire temps. Don't expect to learn everything reading the temps only once. It will take a number of 10 lap sessions to sort everything out that is going on with the tires. When analyzing tire temperatures it should be done in a specific order. This is because a problem in one area may mask a problem in another area. Here is what I do.
Run 10 laps, adjust front cambers. Run another 10 laps.
Adjust tire psi. Run 10 laps.
Adjust toe if needed. Run 10 laps.
Adjust wedge. Run 10 laps..
Adjust for tight or loose condition based on RF & RR average. Run 10 laps.
Look for overheated or overworked tire. Adjust on that corner. Run 10 laps.
Repeat the process all over again. Run 10 more laps.
When checking tire temperatures it is important to make sure your not locking up the brakes or making any sudden changes in your steering outputs. These will all create erroneous tire temperatures readings. Let me try to simplify how to read tire temperatures by giving you this guideline.
A tire with too much NEGATIVE camber will show an excessively higher temperature at the INSIDE edges.
A tire with too much POSITIVE camber will show an excessively higher temperature at the OUTSIDE edges.
A tire that is OVER inflated will have a higher middle temperature than the inside & outside edges.
A tire that is UNDER inflated will have a lower middle temperature than the inside & outside edges.
A car with too much toe OUT will show higher temperatures on both INSIDE edges of the front tires.
A car with too much toe IN will show higher temperatures on both OUTSIDE edges of the front tires.
A RF tire that is HOTTER by more than 10 degrees over the RR indicates a tight condition.
A RF tire that is COLDER by more than 10 degrees over the RR indicates a loose condition.
A tire with the HIGHEST average temperature is the corner of the car that is being most worked.
A tire with the LOWEST average temperature is the corner of the car that is being least worked.
A RF & LR diagonal average that is the same or higher than the front & right side average indicates too much wedge.
A RF & LR diagonal average that is more than 10 degrees lower than the front & right side average indicates not enough wedge.
Let me reiterate once again that the results you see may vary. Using these guidelines will give you a better idea of what your trying to achieve & should get you in the ball park of a quicker more stable setup.
Lets look at a few examples.
RF
I----M----O
208--202--194
Indicates too much negative camber.
RF
I----M----O
194--202--208
Indicates too much positive camber.
RF
I----M----O
204--188--197
Indicates an under inflated tire.
RF
I----M----O
204--210--197
Indicates an over inflated tire.
RF
I----M----O
204--198--194
Indicates correct camber. Overall average temp is 198.6.
RR
I----M----O
227--225--223
Overall average temp. is 225.
If the RR & RF temp above came off the same car we would have a very loose racecar. The RR is approximately 26 degrees hotter than the RF. If this RR is also the hottest tire on the car, it indicates the RR is doing the majority of the work in the corners. This is the corner of the chassis I would work on. We need to take some weight of this corner to cool this tire. I'd start by going with a weaker RR spring. This should cool this tire & tighten up the chassis.
RF
I----M----O
215--192--186
Outside edge is too cool indicating we need more positive camber. Average temp. is 197.6. Let's compare this with the RR below taken on the same car.
RR
I----M----O
190--188--186
Average temp. is 188. This tire is 10 degrees cooler than the RF indicating a neutral handling chassis. This should be good, but we could be faster with a camber change on the RF. Let's adjust the camber on the RF, run another 10 laps & take temps again below.
RF
I----M----O
200--195--190
Camber looks much better now. The average temp is 195.
RR
I----M----O
192--190--188
Average temp. is 190, but now when we compare the average of the RF & RR we find our temperatures too close to each other. After the camber adjustment we no longer have a neutral handling car, but one that is now on the verge of becoming loose. Your general feeling may be that the camber change made the handling worse, and it very well may of. But were still heading in the proper direction. You may have to take a step backwards at 1st to take 2 steps forward later. We can now work on increasing the temp of the RF or work on cooling the RR to increase our average split between the RF & RR. To increase the heat in the RF try a stiffer spring. To decrease the heat in the RR try a weaker spring. Either way you will make the car tighter. How much of a change depends on how much it changes your tire temps. Run another 10 laps & review your temperatures again. Eventually you should be faster than your neutral handling setup with improper camber in the RF.
As you can see from the above example there isn't always an immediate cure. Chassis setup is sort of like solving a puzzle. Experiment & learn as you test. Always keep in mind that you may be going the correct way, but there could be an adjustment elsewhere that may be masking your initial change. Because of this chassis setup can become very frustrating for the novice and experienced alike. For every change you believe your making for the better, it will have an adverse effect elsewhere in the chassis. If for example your car feels great going into & through the middle of a corner, but is loose on exit, you have to tighten it up somehow. Curing the loose condition exiting the corner now has probably messed up your chassis going into the turn. Now you must loosen it up again. It's a constant battle of give & take. Hopefully by monitoring tire temperatures you can eliminate some of the mystery of how & why a chassis is reacting like it does.
Tire Temperature synopsis:
Optimal temp range is between 190-240 degrees.
The hotter the tire the quicker it will wear.
The hottest tire on the car is the tire that is being worked the most. The coolest tire is the least worked.
Work on the corner of the chassis that is either the most overworked or least worked 1st.
A tire with too much NEGATIVE camber will show an excessively higher temperature at the INSIDE edges.
A tire with too much POSITIVE camber will show an excessively higher temperature at the OUTSIDE edges.
A tire that is OVER inflated will have a higher middle temperature than the inside & outside edges.
A tire that is UNDER inflated will have a lower middle temperature than the inside & outside edges.
A car with too much toe OUT will show higher temperatures on both INSIDE edges of the front tires.
A car with too much toe IN will show higher temperatures on both OUTSIDE edges of the front tires.
A RF tire that is HOTTER by more than 10 degrees over the RR indicates a tight condition.
A RF tire that is COLDER by more than 10 degrees over the RR indicates a loose condition.
A tire with the HIGHEST average temperature is the corner of the car that is being most worked.
A tire with the LOWEST average temperature is the corner of the car that is being least worked.
A RF & LR diagonal average that is the same or higher than the front & right side average indicates too much wedge.
A RF & LR diagonal average that is more than 10 degrees lower than the front & right side average indicates not enough wedge.
Track Bar
The track bar or panhard bar as I like to call it, is simply a bar that is mounted behind the rear-end that keeps the rear end from moving from side to side while cornering. The left side of this bar is mounted to the rear-end, while the right side is mounted to the frame. Both of these mounts are adjustable up & down & change the rear roll center of the car. Rear roll center directly effects the body roll experienced in the car.
Within the sim we are allowed to lower the bar as low as 7.00" & raise it as high as 14.00". This measurement in inches is simply telling you how far off the ground the track bar is located. Raising the track bar equally on both ends raises the rear roll center & thus loosens up the car. Lowering the track bar equally lowers the rear roll center & will tighten up the car.
We are also allowed to change the track bar stagger or split between the left & right mounting points. Adding stagger to the track bar changes the angle at which the bar is mounted. By changing the track bar from level, to either uphill or downhill (raising or lower only one side, the LR or RR) you add rear steer to the car. The easiest way to describe rear steer is by equating it with wheel base. If you measure from the center of the wheel at the RF to RR then measure the same on the LF & LR that will give to your wheel base. If one side of your wheel base measurement is NOT the same as the other, you have rear steer. When you add rear steer to the car by running track bar stagger, you change how the chassis will perform at various points throughout a corner.
Raising the right side of the track bar, or lowering the left side, will make the car looser under acceleration while at the same time tighten you up under braking. Of course lowering the right side of the track bar or raising the left side will have the opposite effect & will make the car tighter under acceleration & loosen you up while braking. How much tighter or looser? It depends on how much track bar stagger you have. The greater the angles of the bar, or the larger the difference between the LR & RR, the greater the effect on the chassis.
Track Bar synopsis:
Raising the bar on both ends loosens the chassis.
Lowering the bar on both ends tightens the chassis.
Raising the right side of the bar loosens the car under acceleration, & tightens the chassis under braking.
Lowering the right side of the bar tightens the car under acceleration, & loosens the chassis while braking.
The track notes section of the garage area go hand & hand with the setup notes section. If you haven't yet read the setup notes section please do so now. Proper note taking is the most overlooked aspect of chassis setup. You can never have too many notes. Without proper note taking your always trying to find a needle in a haystack. With proper note taking you will at least know in which part of the haystack to begin your search.
In the track notes section I like to keep track of weather conditions & how they effect the current setup. Was it clear or cloudy when you tested with this setup? What was the temperature? The wind speed & direction? What happens to the chassis under different weather conditions?
I'll also keep track of how I like to enter or exit the corners with the current setup. Making notes of braking & acceleration points with the current setup allows you to know what to expect from the car before hitting the track. What is the best line around the track to take with the current setup? After loading a different setup you should refer to both the setup & track notes sections to review how that setup performs under "such & such" conditions. Enter a race informed of the situation at hand. Unless you've got a photographic memory, proper note taking is the only way to remember all these past adjustments & changes made from track to track. Proper note taking will keep you one step ahead of the competition.
Transmission RatiosThe transmission is designed to change the high rotational speed and low torque (turning force) of the engine's crankshaft into the higher-torque rotation needed to turn the wheels over a range of speeds. Transmission ratios vary through the 4 gears selected during shifting and are adjustable in varying increments for each individual gear. This adjustment can be accessed by clicking the drivetrain/aero tab on the garage screen
Like the differential & transmission ratios, the final drive ratios are read in the same manner. A higher number means a lower (or shorter) gear. Short gearing gives quicker acceleration, but because the engine must turn faster, fuel mileage and top speed are lower. Tall gears give smoother acceleration and higher top speed, at the expense of quick acceleration. NASCAR Racing allows us transmission ratio changes in within following ranges:
1st gear 1.360 - 3.538
2nd gear 1.107 - 2.412
3rd gear 0.885 - 1.938
4th gear 0.885 - 1.667
Transmission ratios are very rarely changed, unless your running at a track that requires a lot of shifting, such as a road course. Most of your ratio changes will be made at the rear end in the differential. The most important factor in selecting proper transmission ratios, is to make sure your not geared to high causing excessive wheel spin. You must also be sure you have a good split between ratios through all 4 gears. You'll want to maintain as high an rpm as possible when shifting through the gears. To large a split ratio between gears will cause slow acceleration and lost time whenever shifting is required. Most notably on a road course & or while exiting the pits.
Transmission Ratio synopsis:
The higher the ratio/number (6.56) the higher the rpm. Provides quicker acceleration, but slower top speeds.
The lower the ratio/number (2.86) the lower the rpm. Provides slower acceleration, but higher top speeds.
For successful gear shifting, remember that it is critical to ensure that all mechanical elements between the drivers hand and the dog faces are in good order and properly set. This includes the gear linkage in the chassis!
Successful up-shifting, (defined as fast and non dog-damaging) will be achieved by fully moving the dog ring as rapidly as possible from one gear to the next, preferably with the engine's driving load removed until the shift is completed. (The opposite is true of a synchromesh gearbox as used in passenger cars, where slow movement helps). It should be remembered that it is not possible to damage the dogs when fully engaged (in gear). The damage can only take place when initiating contact during a shift, (the `danger zone`) therefore this element must be made as short as possible. If a driver moves the gear lever slowly, or if the linkage is not rigid and effective, dog wear will occur. We always recommend lightweight yet solid rod linkage, not cables ideally.
I list below the different methods of up-shifting that are used in racing most commonly. The best at the top, the worst at the bottom:
Automated (semi automated). The movement of the dog ring is powered and the engine is cut / re-instated in a co-ordinate manner. Gear-shifts take milliseconds. This system produces zero dog wear when set up well. It is not applicable to most cars, but it illustrates that speed of shift is a good thing.
Manual with engine cut. This system is almost as good as an automated one as long as the driver pulls the lever very quickly. Again it is not applicable to many cars, but it illustrates that speed of shift is a good thing. A `cheat` version of this is to shift on the engine rev limiter, which can work well. With this system it is especially important to move the lever ultra fast, otherwise the engine will be reinstated during partial dog engagement, causing damage. The damage can usually be felt by the driver.
ManualBest method:
With no assistance from the engine management, the driver must lift off the throttle sufficiently to allow the dog ring to be pulled out of engagement. He should then stay off the throttle long enough to allow the dog ring to engage with the next gear. In practice, the driver can move the gear lever faster than he can move his foot off and back on to the throttle. Therefore the effective method is to apply load to the gear lever with your hand and then lift the throttle foot off and back on to the pedal as fast as physically possible. In lifting your foot, the loaded gear lever will almost involuntarily flick to the next gear before the foot is re-applied to the throttle.
Another method is to load the gear lever with your hand, stay flat on the throttle and dab the clutch to release the dog ring. The overall effect on the gear shift is similar to the above method, but clutch wear may become a big issue.
The worst method (most destructive and definitely slowest) is to attempt to change gear in a `passenger car / synchromesh` way, i.e. lifting off the throttle, dipping the clutch, moving the gear lever, letting the clutch up and re-instating the throttle. The method causes unnecessary clutch wear, does absolutely nothing to help come out of gear and usually causes dog wear whilst engaging the next gear. This wear is due to several reasons. Firstly, it is impossible for a driver to co-ordinate the complicated sequence of all five physical movements accurately. Consequently the engagement dogs often find themselves engaging whilst the throttle is applied. The lever is usually pulled more slowly as it was not pre-loaded, lengthening the `danger zone`.
Successful down-shifting, has similar rules applied regarding speed of shift. Unloading the dogs is done in the opposite manner obviously. Whilst braking, the dogs must be unloaded by either touching the throttle pedal or- my preferred method- by dipping the clutch. However, one sharp dab of clutch or throttle is appropriate per shift. Continued pressure on either will cause dog damage for different reasons. `Blipping the throttle` just before engagement is advisable if the rev drops between gears are over 1300 rpm, as this will aid engagement and stabilize the car.
TOP TIP for ease of downshifting: Make the downshifts as late as possible in your braking zone (i.e. at lower road speed), because the rev drops between each gear are then lower. So many drivers make the mistake of downshifting as soon as they begin braking, causing gearbox wear, engine damage and `disruption` to the driving wheels.
Wedge
The wedge can be adjusted by clicking the weight bias tab on the garage screen. Wedge is also known as cross weight or diagonal weight. Wedge is the total weight of the RF & LR corners divided by the cars total weight. Wedge is used to keep the back of the car tight entering a corner while also adding bite exiting a corner.
Within NASCAR Racing, wedge can be adjusted as low as -150lbs. (47.9%) to as high as 150lbs. (52.1%).
The total amount of wedge required depends on track size & roll couple in the car. A setup that will spin it's tires easily will require more wedge to counter act the traction loss under power. A setup with a higher gear ratio or one that does not spin the tires will require less wedge. Wedge is required to get through the corners. Excessive amounts of wedge can slow the car down & wear the RF & LR tires prematurely.
Where as changing the front & left side bias is done by moving lead ballast, changing the wedge is done by screwing up or down on load bolts located over the RF & LR springs. You might think that by changing wedge you would change left side or front bias, but that isn't the case. No matter how you adjust the wedge the left & front bias will always remain the same. Increasing wedge will tighten the chassis. Decreasing wedge will loosen the chassis.
Wedge synopsis:
Increasing wedge tightens the chassis.
Decreasing wedge loosens the chassis.
Steering Linearity
I believe it is important to bring up the subject of steering linearity in this chassis guide although it really isn't a garage/chassis option. Steering linearity can effect the way your car performs through the corners. You can adjust your steering linearity under the options/controls tab within NASCAR Racing. You are allowed a range of adjustment from 0% Non-linear to 100% Linear.
The reason this option is available to use is because of all the available steering devices on the market. Although I don't suggest it, you are able to race with a joystick, as well as every type of wheel device you can imagine. Not all steering devices are created equal. Various manufactures provide different degrees of wheel movement. In other words, while one steering device may take you a quarter turn to negotiate a corner at Michigan, another wheel manufacture may require a half turn on the steering wheel to negotiate that same corner with the same exact steering ratio & linearity settings. Steering linearity allows us an adjustment to compensate for the differences in steering devices. As a general rule, most steering wheel devices will provide better precision when set towards a higher linear setting than low. Joystick users would probably prefer a lower non-linear setting.
With 100% linear steering, the wheels always turn an even amount of degrees relative to how you turn your controller. With non-linear steering, the steering is slower when the controller is close to center position and progressively quickens the more you turn the controller. At 100% linear, you will be required to steer less, but the steering will be a lot more sensitive or twitchy with the slightest of steering input. At a lower or non-linear setting, you will need to turn your wheel more to enter a corner, but you may experience a more comfortable feel, which will allow you to make better or more accurate steering decisions.
There is no right or wrong answer when it comes choosing the proper steering linearity. It all depends on what the driver is more comfortable with & what works best with what steering device you are using. A loose setup may work better with a different linearity setting than a tight setup. Adjusting your linearity can change your lap times for the better or worse. It can also change your tire wear for the better or worse. Adjusting your steering ratio along with your linearity will provide you with even more or less steering feedback.
Don't be afraid to experiment with this option. You may find a certain comfort zone with a certain linearity setting & stick with it from here on out. You may find yourself changing your linearity settings based on how tight the turning radius is for the track your competing at. Either way, experimentation is the only way your going to find out what is comfortable for you.
Qualifying Chassis Adjustments
There are two distinct differences in NASCAR Racing as compared to N4; first, we now get two laps of qualifying at every oval track, second, we have to use the race motor. Even though we get two laps, we shouldn t waist the first lap for any track except the superspeedways. Often times you ll find that the first lap is the quickest.
There are probably two main philosophies about qualifying setups; we could build something that's very radical but it drives much differently than our race setup or we could build something that basically drives the same as our race setup but we take advantage of the fact that we re not concerned with tire wear at all so we build a setup that we can drive hard for two laps and not have to worry about changing our driving style that much. I prefer that latter philosophy. The next section talks about the chassis adjustments I may make and the order I make them.
Chassis Adjustments:
Tire Pressures: The first thing we want to do is add some tire pressure to reduce rolling drag and bring the temps up quicker so we get maximum bite. We don t want to raise tire pressures so much though that we lose bite because we ve severely reduced the tires contact patch by crowning it too much. The tire model in NASCAR Racing is much more realistic than it was in N4 and not having enough contact patch is much more apparent. Typically, we want the tires to crown about 4-6 degrees.
Tape: Next we add tape but at most tracks you re not going to be able to tape the whole grille up or you ll blow the motor before you ve completed two laps. As a matter of fact, you ll want to baby the car through the gears as you re pulling off pit lane. Remember that adding tape increases front down force which will loosen the car up some.
Wedge: If you use any negative wedge on your race setup, put the wedge back to neutral which will offset the added down force of increased tape.
Final Drive ratio: I use a taller 4th gear than I think I need especially at the short tracks where rear wheel spin can rob you of serious time. DO NOT use rear wheel spin to turn the car during qualifying. If the rev idiot light comes on at the end of the straights, 4th gear is too short. A chassis that pushes on exit also robs you of time. Use the front sway bar to fine tune that.
Camber: In NASCAR Racing, the true measure of camber may not show up for 15 or more laps and we already know that we don t want our tire temp spread to be any more that 10 degrees across the tire for maximum grip. (Again, this is much improved over N4) So for qualifying we may want to add a bit more negative camber to the RF and positive to the LF.
Forward Weight: Since we have the car gripping a little better up front because of the tape and camber and we re probably going to enter the corners a bit faster, we may want to move weight forward a little for stability on corner entry. We don t want to make drastic changes here or it will throw off how the car handles in the middle, therefore how we drive the car.
Rear Spring split: To overcome moving weight forward and increased corner entry speeds, I increase the split in the rear springs which further stabilizes the car on entry and helps the car turn better from the middle off. For race setups, I use very little rear split because as the RF tire wears a big rear split has a tendency to make the car snap loose on exit.
Springs: Stiffer springs can give you slightly better straight speeds but at the cost of handling. If you do stiffen or soften the springs, you ll want to do evenly on all 4 corners to keep the chassis handling about the same. You can measure this by using roll couple.
Shocks: If anything, I may increase the compression stiffness of the RF shock which allows the weight to stay on the left a little longer remembering that we really don t care about tire wear here. For race setups, a stiff RF compression will cause the RF to scrub more thereby wearing it out quicker.
Sway bars: I may increase the front sway bar some if the car is a little too loose. Roll couple does not matter in a qualifying setup except that drastically changing the roll couple will change the overall handling characteristics of the car. Remember our goal through this whole process is to make the car quicker but not change how we drive it very much if at all.
Rear Spoiler: I use 70 degrees everywhere except at Atlanta, Lowes, and Michigan. Those tracks have straights long enough and the corners are banked enough to warrant the decreased drag at the expense of down force. (55 degrees is mandated at the Dega and Daytona)
Ride height: I normally don t mess with this except as a last resort when I want the car to be just a tad looser or tighter. Lower is now better as it should be in NASCAR Racing but wasn t necessarily the case in N4.
Caster: The very last thing I change because I normally have the way I want it from my race setup.
From a driving standpoint, we re not concerned with tire wear but remember that sliding the car (excessive squealing of the tires) through the corners robs you of time. You definitely have to have the mindset of driving the car as hard as possible but even smoother than you do during a race. You may have to slightly adjust you re braking/entry points to maintain mid corner speeds. Concentration and driver ability will be much more important than changing the chassis in NASCAR Racing.
TROUBLESHOOTING
Chassis adjustments & possible causes
This section will list excessive chassis adjustments & what there effect on the chassis & or handling of the car will be. Please use this section only as a general guide. You may not see the same exact results as mentioned below. Other component settings may mask changes made in different areas. Adjustments in other areas may be needed first before you see some of the changes indicated below in certain areas. All troubleshooting answers assume the rest of the chassis is already set correctly or close to being correct.
CAMBER
Too much negative RF camber:
Inside of tire excessively hot.
Car turns into a corner too quickly or becomes loose.
Too much negative LF camber:
Inside of tire excessively hot.
Reduced pull to the left entering a corner.
Chassis will tighten up from the middle out.
Too much negative RR camber:
Inside of tire excessively hot.
Tight condition from the middle out.
Too much negative LR camber:
Inside of tire excessively hot.
Loose condition entering a corner.
Too much positive RF camber:
Outside of tire excessively hot.
Car turns into a corner too slowly & feels tight.
Too much positive LF camber:
Outside of tire excessively hot.
Increased pull to the left entering a corner.
Chassis will loosen up from the middle out.
Too much positive RR camber:
Outside of tire excessively hot.
Loose condition from the middle out.
Too much positive LR camber:
Outside of tire excessively hot.
Tight condition entering a corner.
CASTER
Too much caster:
Car is more difficult to steer, more effort is required. (more noticeable with a force feedback wheel)
Car will tend to loosen up the more the wheel is turned.
Not enough caster:
Car too sensitive, steering becomes twitchy.
Very little steering feel, less effort is required to turn. (more noticeable with a force feedback wheel)
Excessive caster stagger:
Harder to steer in one direction than the other.
Car will pull towards the side with less caster.
Car will feel loose entering a corner.
DIFFERENTIAL RATIO
Too high a ratio:
High rpms, potential for a blown engine.
Loss of traction or wheel spin when accelerating.
Loss of top speed at the end of a straight-away.
Too low a ratio:
Low rpms.
Car feels sluggish upon acceleration.
Car feels under powered.
FRONT BIAS
Too much front bias:
Will cause car to push.
Not enough front bias:
Will cause car to be loose.
FRONT BRAKE BIAS
Too much front brake bias:
Will cause car to push while braking.
Not enough front brake bias:
Will cause car to become loose while braking.
FRONT SWAY BAR
Too large a bar:
Car feels stiff, unstable & does not roll while cornering.
Car pushes through the corners.
Front may tend to slide & not take set.
Car may get tighter as you progress through turn.
Too small a bar:
Car rolls excessively while cornering & could bottom out on the RF.
Back of the car is hard to control & feels real loose.
Car is slow to respond when changing directions.
FRONT TOE OUT
Too much toe out:
Car feels difficult to turn into corner.
Car may not take set in the corner.
Car will want to push.
Car may wander under heavy braking.
Too much toe in:
Car turns into a corner quicker than it should with very little wheel movement.
Car will feel loose upon entry into a corner & is generally unstable.
GRILL TAPE
Too much tape:
Water temperature will rise. Potential engine damage.
Increased speeds
Front end will stick extremely well causing a loose condition.
Not enough tape:
Cool engine temperatures.
Slower top speeds.
Little or no front down force will cause the car to push.
LEFT BIAS
Too much left bias:
Will cause car to pull to the left.
Car will turn left much easier than right.
Car will loosen itself up when negotiating left hand turns.
Not enough left bias:
Car will not turn left into a turn as easy.
Car will turn right much more easier.
Car will feel tight when negotiating left hand turns.
REAR SWAY BAR
Too large a rear sway bar:
Car will feel loose
May feel excessive wheel spin on exit.
Too small a rear sway bar:
Car will feel tight.
RIDE HEIGHT
Too low a ride height:
Car will bottom out.
On the RF, LF, & RR the car will feel loose.
On the rear will increase straightaway speeds.
Too high a ride height:
On the LR will loosen the chassis.
On the LR may cause the RF to bottom out.
On the RF will tighten the chassis.
On the rear will increase rear traction & bite.
SHOCKS
Front shocks too stiff:
Car will push entering the corner while braking.
Car will also push while accelerating exiting a corner.
Front shocks too weak:
Car will be loose entering a corner while braking.
Car will also feel loose exiting a corner while under acceleration.
Rear shocks too stiff:
Car will be loose entering a corner while braking.
Car will also feel loose exiting a corner while under acceleration.
Rear shocks too weak:
Car will push entering the corner while braking.
Car will also push while accelerating exiting a corner.
SPOILER
Too high a spoiler:
You'll notice slower straight-away speeds.
Chassis will feel tight while cornering.
Too low a spoiler:
Quicker straight-away speeds.
Chassis will feel loose while cornering.
SPRINGS
Front springs too stiff:
Car will Under steer.
Car feels stiff & unresponsive.
Front springs too weak:
Car will Under steer.
Front of car will dive entering a corner & may bottom out while braking.
Excessive body roll.
Mid turn push.
Rear springs too stiff:
Car will Over steer when accelerating.
Excessive wheel spin.
Rear springs too weak:
Car will Under steer.
Excessive rear squat when accelerating possibly bottoming out.
Car will roll over onto the RR.
Car may be slow to take a set.
RF too stiff:
Car will push or Under steer.
RF too weak:
Car will be loose or Under steer.
LF too stiff:
Car will be loose or Under steer.
LF too weak:
Car will push or Under steer.
RR too stiff:
Car will be loose or Under steer.
RR too weak:
Car will push or Under steer.
LR too stiff:
Car will push or Under steer.
LR too weak:
Car will be loose or Under steer.
STEERING RATIO
Too high a ratio:
Slow steering response.
More steering required to negotiate a corner.
Too low a ratio:
Quick steering response.
Very little steering needed to negotiate a corner.
Car feels sensitive or twitchy.
TIRE PRESSURE
Front pressure too low:
Excessive heat in tire.
Car will Under steer.
Front pressure too high:
Cooler tire temperatures.
Higher temp. in the middle of the tire.
Rear pressure too low:
Excessive heat in tire.
Car will Over steer.
Rear pressure too high:
Cooler tire temperatures.
Higher temp. in the middle of the tire.
RF too high:
Car will feel loose.
RF too low:
Car will feel tight.
RR too high:
Car will feel loose.
RR too low:
Car will feel tight.
LR too high:
Car will feel tight from the middle out.
LR too low:
Car will feel loose from the middle out.
LF too high:
Car will feel tight.
LF too low:
Car will feel loose.
TRACK BAR
Too low:
Car will roll less.
Car will Under steer or feel tight.
Too high:
Car will roll more.
Car will Over steer or feel loose.
Right side too low:
Car will feel loose entering a corner while braking.
Car will push exiting a corner while accelerating.
Right side too high:
Car will push entering a corner while braking.
Car will feel loose exiting a corner while accelerating.
TRANSMISSION RATIO
Too high a ratio:
High rpms, potential for a blown engine.
Loss of traction or wheel spin when accelerating.
Loss of top speed at the end of a straight-away in 4th gear.
Too low a ratio:
Low rpms.
Car feels sluggish upon acceleration in 4th gear.
Car feels under powered.
WEDGE
Too much:
Car will push.
Prematurely worn RF & LR tires.
Not enough:
Car will be loose.
RF & LR tires not carrying there fair share of the load.
Handling problems & possible causes
This section will list various handling problems & what might be causing those handling problems. Please use this section only as a general guide. You may not see the same exact results as mentioned below. Other component settings may mask changes made in different areas. Adjustments in other areas may be needed first before you see some of the changes indicated below in certain areas. All troubleshooting answers assume the rest of the chassis is already set correctly or close to being correct.
CAR FEELS UNSTABLE
Excessive front toe.
Too soft a shock.
Too much camber stagger.
Excessive front or rear bias.
Not enough caster
Excessive caster stagger.
Front sway bar too stiff.
Excessive front or rear brake bias.
Fuel load had changed.
Too much grill tape.
Too low a ride height
Spoiler too low.
Wrong spring.
Steering ratio too low.
Steering linearity too high.
Tire psi. too low.
CAR FEELS UNRESPONSIVE
Tire psi too low.
Springs too soft.
Shocks too soft.
Front sway bar to small.
Track bar too high.
Too much caster
CAR FEELS OVER RESPONSIVE
Tire psi too high.
Springs too stiff.
Shocks too soft.
Front sway bar to large.
Track bar too low.
CAR IS LOOSE ENTERING CORNER
Too much stagger.
Not enough toe out.
Too much negative RF camber.
Too much positive LF camber.
RR camber too high.
Too much caster stagger.
RF caster too high.
Not enough front brake bias.
Not enough front bias.
Front sway bar too small.
Too much grill tape.
Too large a rear sway bar.
LR ride height too high.
LR shock rebound too stiff.
LF shock compression too soft.
RR shock rebound too stiff.
Front shock compression too soft.
Rear shock rebound too stiff.
Spoiler angle too low.
Front springs too weak.
Front spring stagger to high.
Rear springs too stiff.
RF spring too soft.
RR spring too stiff.
Front spring stagger too high.
Steering ratio too high.
RF tire psi. too high.
RR tire psi. too high.
LF tire psi. too low.
RF caster too high.
Track bar too high.
Right side track bar too low.
Wedge too low.
Too much trail braking.
Driver error. (erratic throttle & steering inputs)
CAR IS LOOSE IN THE MIDDLE OF A CORNER
Wedge too low.
RF spring too soft.
RR spring too stiff.
Too much rear spring stagger.
Front sway bar too soft.
RR psi. too high.
Stagger too high.
Track bar too high.
Front tire psi. too high.
LR tire psi. too low.
Excessive front toe (in or out)
Improper camber settings.
Not enough negative LF camber.
Excessive positive camber in the RR.
Too much positive caster.
Too high a differential ratio causing wheel spin.
LF shock compression too low.
LR shock rebound too high.
RR shock compression too high.
Right side track bar too high. (too much split on banked tracks)
Left side track bar too high, (Not enough split on flat tracks)
Not enough front bias.
Spoiler too low.
Driver error. Compensating for a corner entry push.
CAR IS LOOSE EXITING A CORNER
Too much stagger.
Wedge too low.
LF caster too low.
Too much positive LF camber.
LR spring too soft.
RR spring too stiff.
Decrease rear spring stagger.
RR tire psi. too high.
LR tire psi. too low.
Too high a differential ratio causing wheel spin.
Not enough front bias.
Too small a front sway bar.
Excessive front toe (in or out).
Too much grill tape.
Too large a rear sway bar.
LR ride height too high.
Rear shock compression too stiff.
Front shock rebound too soft.
Spoiler too low.
Rear spring stagger too high.
Front springs too weak.
Rear springs too stiff.
Track bar too high.
Track bar on right side is too high.
Driver error. (erratic throttle & steering inputs)
CAR PUSHES ENTERING CORNER
Not enough stagger.
Too much toe out.
Not enough negative RF camber.
Not enough positive LF camber.
Not enough caster stagger.
Too much front brake bias.
Too much front bias.
Front sway bar too large.
Not enough grill tape.
Too small a rear sway bar.
LR ride height too low.
LR shock rebound too weak.
Front shock compression too stiff.
Rear shock rebound too weak.
Spoiler angle too high.
Front springs too stiff.
Front spring stagger to low.
Rear springs too weak.
RF spring too stiff.
RR spring too soft.
Front spring stagger too low.
Steering ratio too low.
RF tire psi. too low.
RR tire psi. too low.
LF tire psi. too high.
RF caster too low.
Track bar too low.
Right side track bar too high.
Wedge too high.
Driver error.
CAR IS TIGHT IN THE MIDDLE OF A CORNER
Wedge too high.
RF spring too stiff.
RR spring too soft.
Not enough rear spring stagger.
Front sway bar too stiff.
RR psi. too low.
Stagger too low.
Track bar too low.
Front tire psi. too low.
LR tire psi. too high.
Excessive front toe (in or out)
Improper camber settings.
Too much negative LF camber.
Not enough positive camber in the RR.
Not enough positive caster.
Too low a differential ratio.
LF shock compression too high.
LR shock rebound too low.
RR shock compression too low.
Right side track bar too low. (not enough split)
Too much front bias.
Spoiler too high.
Driver error. Compensating for corner entry looseness.
CAR PUSHES EXITING A CORNER
Not enough stagger.
Wedge too high.
LR spring too stiff.
RR spring too soft.
RR tire psi. too low.
LR tire psi. too high.
Too low a differential ratio.
Too much front bias.
Too large a front sway bar.
Excessive front toe (in or out).
Not enough grill tape.
Not enough positive LF camber.
Too small a rear sway bar.
LR ride height too low.
Rear shock compression too soft.
Front shock rebound too stiff.
RR shock compression too low.
Spoiler too high.
Rear spring stagger too low.
Front springs too stiff.
Rear springs too soft.
Track bar too low.
Track bar on right side is too low. (not enough split)
On Track Adjustments
This section will discuss the adjustment options we have available to us during a race while pitting.
Once the race begins, were limited as to what we can adjust to help improve our chassis.
The following is a list of options we can change during a pit stop:
F3 Fuel
F5 Tires/psi.
F6 Wedge
F7 Track Bar
F8 Grill Tape
To change the amount of fuel you would like during a pit stop you must press the F3 button on your keyboard. From here you can use you left & right arrows to select how much fuel you want to take on. You are allowed to take on a splash of fuel as well as 1/2, 1, 1 1/2, or 2 cans. A splash of fuel will give you 2-3 gallons. 1/2 can gives you 5-6 gallons. 1 can equals 11-12 gallons, 1 1/2 cans will give you 17-18 gallons. 2 cans will fill your tank with 22 gallons. The less fuel you carry the faster you should be. Use this to your advantage when planning pit stops, race strategy, & fuel mileage.
Pressing the F5 button on your keyboard will bring up the tire change screen. Here you are able to decide how many tires you would like changed as well as any psi adjustments you would like to make. Pressing the space bar will allow you to toggle between taking on 4 tires, left sides, right sides or no tires. Using the up & down arrows on the keyboard will allow you to select each individual tire that you would like to make an air pressure adjustment too. Hitting the left & right arrows will allow you to increase or decrease the pressure of the selected tire in 1/2 lb. increments. Tire psi is the most difficult of all adjustments to remember while pitting because it can be changed in conjunction with other tires to produce various results.
The F6 button on your keyboard will allow you to make a wedge adjustment. Use the left & right arrows to increase or decrease the desired amount of wedge. You can change the wedge in 5 lb. increments. Increasing wedge (higher %) will tighten the chassis. Decreasing wedge (lower%) will loosen the chassis.
Use the F7 button to adjust your track bar. Using the left & right arrows we can raise or lower the track bar in 1/4" increments. The important thing to remember when adjusting the track bar during a pit stop, is that your raising or lower the RIGHT side ONLY. In the garage were allowed adjustments on both sides. Because were only adjusting the right or frame side of the track bar, we are adding rear steer to the chassis. Therefore raising the the track bar during a pit stop will make the car looser under acceleration while at the same time tighten you up under braking. Lowering the right side of the track bar will have the opposite effect & will make the car tighter under acceleration & loosen you up while braking. The more you raise or lower the bar, the greater the effect on the chassis.
Adding or removing grill tape is another adjustment we can make by using the F8 button on the keyboard. The left & right arrows will add or subtract tape in 5% increments. Adding grill tape reduces drag & increases speed. Adding tape also places more down force on the front end & can be used to loosen the car up through the corners. Be sure to keep an eye on your gauges. Too much tape will raise your water temperature & overheat your engine, you might be forced to make an extra pit stop to remove the tape to help cool the engine.
As you can see, the number of adjustments we have available to us during a race, are far less than we have in the garage. Because of this it is important to have your setup close before entering a race. Use the above adjustments to fine tune the chassis for the various weather conditions & to readjust your chassis as a race progresses.
Troubleshooting by component
This section will discuss each adjustable chassis component & there effect on the handling of the car. Please use this section only as a general guide. You may not get the same exact results as mentioned below. Other component settings may mask changes made in different areas. Adjustments in other areas may be needed first before you see some of the changes indicated below in certain areas. All troubleshooting answers assume the rest of the chassis is already set correctly or close to being correct.
Camber
More negative RF camber allows the car to turn into a corner quicker & will loosen up the chassis.
Less negative RF camber takes away some of the pull to the left. The car won't turn in as quicker into a corner & will tend to tighten the chassis.
More negative LF camber will reduce the pull to the left while tightening the chassis from the middle out.
More positive LF camber will increase the pull to the left & allow the car to turn into a corner quicker loosening the chassis.
More positive camber in the RR will loosen the car from the middle out.
More negative camber in the LR will loosen the chassis entering a corner.
Caster
More positive caster will loosen the chassis the more the wheel is turned through a corner.
Caster adjustments are better felt through a force feedback wheel.
The car will pull to the side with the lower amount of positive caster.
The higher the caster stagger, the easier the car will turn into a corner.
The higher the caster stagger, the less steering effort required. This will tend to give you a loose feeling upon corner entry.
Differential Ratio
The higher the ratio/number (6.56) the higher the rpms. Provides quicker acceleration, but slower top speeds.
The lower the ratio/number (2.86) the lower the rpms. Provides slower acceleration, but higher top speeds.
Final Drive Ratios
The higher the ratio/number the higher the rpms. Provides quicker acceleration, but slower top speeds.
The lower the ratio/number the lower the rpms. Provides slower acceleration, but higher top speeds.
Front Bias
More front bias will tighten the chassis.
Less front bias will loosen the chassis.
Front Brake Bias
More front brake bias will tighten the chassis entering a corner under braking.
Less front brake bias will loosen the chassis entering a corner under braking.
Front Sway Bar
The larger the bar the tighter the chassis.
The smaller the bar the looser the chassis.
Front Toe Out
Excessive front toe out will make a car turn slower into a corner, & cause a tight condition.
Excessive front toe in will make a car turn into a corner quicker, & may create a loose condition.
Fuel Level
Less fuel equals faster speeds.
The less fuel in the tank the tighter the chassis will become.
Splash = 2-3 gallons, 1/2 can = 5-6 gallons, 1 can = 11-12 gallons, 1 1/2 cans = 17-18 gallons, 2 cans = full tank.
Grill Tape
Higher tape % will increase speeds.
Higher tape % equals higher water temperatures.
Higher tape % will loosen the chassis.
Left Bias
Higher left side bias will help turn the car left into a corner & loosen a chassis when making left hand turns.
Higher right side bias will cause the car to Under steer when making a left hand turn.
Rear Sway Bar
The larger the bar the looser the chassis.
The smaller the bar the tighter the chassis.
Ride Height
Too low a ride height could cause the car to bottom out.
The higher the RF ride height the tighter the car will be.
The higher the REAR ride heights, the more drag on the straight-away, but the better the rear will stick in the corners.
A higher LF will tighten the chassis.
A higher LR will loosen the chassis.
A higher RR will tighten the chassis.
Shocks
LF
Higher compression will tighten the chassis entering a corner.
Lower compression will loosen the chassis entering a corner.
Higher rebound will tighten the chassis accelerating out of a corner.
Lower rebound will loosen the chassis accelerating out of a corner.
RF
Higher compression will tighten the chassis entering a corner.
Lower compression will loosen the chassis entering a corner.
Higher rebound will tighten the chassis accelerating out of a corner.
Lower rebound will loosen the chassis accelerating out of a corner.
LR
Higher compression will loosen the chassis accelerating out of a corner.
Lower compression will tighten the chassis accelerating out of a corner.
Higher rebound will loosen the chassis entering a corner.
Lower rebound will tighten the chassis entering a corner.
RR
Higher compression will loosen the chassis accelerating out of a corner.
Lower compression will tighten the chassis accelerating out of a corner.
Higher rebound will loosen the chassis entering a corner.
Lower rebound will tighten the chassis entering a corner.
Asymmetrical changes:
The stiffer the shock, the less grip that tire will have.
Stiffer rebound on the left shocks will help the car turn in by slowing weight transfer to the right.
Stiffer compression on the right shocks will help the car turn in by also slowing weight transfer to the right.
Softer rebound on the front shocks will loosen the chassis exiting the corner.
Softer compression on the rear shocks will tighten the chassis exiting the corner.
Doing just the opposite mentioned above, on either compression or rebound will produce just the opposite results.
Asymmetrical changes seem to have a greater influence than individual shock changes.
General:
Use the above info as a guideline only. Changing just one shock may not give you the exact results mentioned above. Other factors must be considered. Other shocks & settings as well as asymmetrical changes will produce different results with varying degrees of chassis changes or feelings based on other components & driving style.
Spoiler
The higher the angle the slower your straight-away speeds.
The lower the angle the faster your straight-away speeds.
The lower the angle the looser the chassis.
The higher the angle the tighter the chassis.
Springs
Weaker LF will make the car tight.
Weaker RR will make the car tight.
Weaker RF will make the car loose.
Weaker LR will make the car loose.
Stiffer RF will make the car tight.
Stiffer LR will make the car tight.
Stiffer LF will make the car loose.
Stiffer RR will make the car loose.
Overall stiffer front springs will make the car tight.
Overall stiffer back springs will make the car loose.
Overall weaker front springs will make the car loose.
Overall weaker back springs will make the car tight.
Increasing front spring stagger will tighten the car under acceleration & loosen it under braking.
Increasing rear spring stagger will loosen the car under acceleration & tighten it under braking.
Steering Ratio
The lower the ratio the quicker the steering response.
The higher the ratio the slower the steering response.
Lower ratios require less turning of the wheel to negotiate a corner.
Higher ratios require more turning of the wheel to negotiate a corner.
Tire Pressure
Higher psi in RF will loosen the car.
Lower psi in the RF will tighten the car.
Higher psi in RR will loosen the car.
Lower psi in the RR will tighten the car.
Higher psi in the LR will tighten the car from the middle out.
Lower psi in the LR will loosen the car from the middle out.
Higher psi in the LF will tighten the car.
Lower psi in the LF will loosen the car.
The lower the psi in a tire the hotter it will run.
The higher the psi in a tire the colder it will run.
Excessively low front tire psi will create a push.
Excessively low rear tire psi will create a loose condition.
Increasing the split (more RR psi than LR) increases stagger, helping the car to turn in the middle of a corner.
Increasing the split of the left & right side psi (more psi on the right) increases the pull to the left.
Tire Temperatures
Optimal temp range is between 190-240 degrees.
The hotter the tire the quicker it will wear.
The hottest tire on the car is the tire that is being worked the most. The coolest tire is the least worked.
Work on the corner of the chassis that is either the most overworked or least worked 1st.
A tire with too much NEGATIVE camber will show an excessively higher temperature at the INSIDE edges.
A tire with too much POSITIVE camber will show an excessively higher temperature at the OUTSIDE edges.
A tire that is OVER inflated will have a higher middle temperature than the inside & outside edges.
A tire that is UNDER inflated will have a lower middle temperature than the inside & outside edges.
A car with too much toe OUT will show higher temperatures on both INSIDE edges of the front tires.
A car with too much toe IN will show higher temperatures on both OUTSIDE edges of the front tires.
A RF tire that is HOTTER by more than 10 degrees over the RR indicates a tight condition.
A RF tire that is COLDER by more than 10 degrees over the RR indicates a loose condition.
A tire with the HIGHEST average temperature is the corner of the car that is being most worked.
A tire with the LOWEST average temperature is the corner of the car that is being least worked.
A RF & LR diagonal average that is the same or higher than the front & right side average indicates too much wedge.
A RF & LR diagonal average that is more than 10 degrees lower than the front & right side average indicates not enough wedge.
Track Bar
Raising the bar on both ends loosens the chassis.
Lowering the bar on both ends tightens the chassis.
Raising the right side of the bar loosens the car under acceleration, & tightens the chassis under braking.
Lowering the right side of the bar tightens the car under acceleration, & loosens the chassis while braking.
Transmission Ratios
The higher the ratio/number (6.56) the higher the rpms. Provides quicker acceleration, but slower top speeds.
The lower the ratio/number (2.86) the lower the rpms. Provides slower acceleration, but higher top speeds.
Wedge
Increasing wedge tightens the chassis.
Decreasing wedge loosens the chassis.
Glossary
Aero-Loose: An over steer or loose condition created when a car follows to too closely. The car behind you takes air off your spoiler giving you little or no down force on the rear of of car. The result is a car that all the sudden becomes very loose.
Aero-Push: An under steer or tight condition created when you follow a car too closely. The car in front of you takes air off the front of your car giving you little or no down force on the front of your car. The result is a car that all the sudden becomes tight or pushes.
Apex: The area of a corner, not just a clipping point, where the inside front wheel runs closest to the inside of a given corner. Where you apex is directly related to how you entered at the turn and will effect how you exit the turn. An apex varies from corner to corner and, for example can be too early or to late.
Apron: The paved flat surface that separates the racing surface from the infield.
Blend Line: The painted white or yellow line that you must stay below before merging into traffic when exiting the pits.
Camber: Camber is the inward or outward tilt of the wheel at the top of the wheel.
Caster: Caster is the leaning forward or back of the tire at the top of the wheel.
Cross Weight: the total weight of the RF & LR corners divided by the cars total weight.
Diamond: A method of cornering where you have an early apex entry into turns 1 & 3, followed by a late apex exit from turns 3 & 4. This line forms a diamond and is preferable at certain tracks.
Drifting: Drifting is or should be a controlled function, it is a balance. It is directly opposed to sliding or skidding which are out-of-control conditions.
Dynamic weight transfer: Is the transferring of weight from side to side during cornering, from rear to front during deceleration and from front to rear during acceleration.
Groove: The groove is usually considered the fastest way around the race track. It is visible by the darkened asphalt around the racing surface.
Line: This refers to the physical line of movement that car car takes through any given turn from entry, to apex, to exit. A line can be either good or bad, right or wrong.
Over steer: When you have adhesion and traction with the front wheels of the car, but the rear wheels lose traction and slide toward the front. It is also referred to as being "loose" or "coming around."
Panhard Bar: A bar that is mounted behind the rear-end that keeps the rear end from moving from side to side while cornering.
Ride Height: The distance measured in inches from the bottom of the frame rails to the ground.
Roll Center: The point about which the car rolls.
Roll Couple: The percentage of how much body roll is distributed between the front and the rear suspension systems.
Rear Steer: When the rear wheels decrease wheel base on one side & increase on the other.
Stagger: The difference in circumference between the right side tires & left.
Takes set: A term used in cornering when all weight transfer has taken place and the tires are at maximum slip angles.
Traction Sampling: Periods when you are in danger of exceeding the limits of tire adhesion, such as when cornering, braking, and accelerating.
Trail Braking: Trail braking occurs anytime your turning and decelerating (not necessarily braking), at the same time.
Trailing Throttle Over steer: A condition when the back of the car wants to pass by the front entering a corner. A car that becomes loose usually due to abrupt throttle and brake transitions. Trailing throttle over steer is caused by quickly letting of the throttle or hitting the brakes too hard turning into a corner. When this occurs, all the weight from the car is being transferred towards the front of the vehicle. This causes the back of the car to become light or loose and most likely results in a spin. This is the most common mistake made by rookie drivers.
Under steer: When you have traction with the rear wheels but the front wheels lose traction regardless of the steering correction. Also referred to as "pushing" or "plowing."
Wheel Base: The distance as measured from the center of the front wheel to the center of the rear wheel.