Race car suspension setup guide

Because too much positive caster also has it's drawbacks. When you turn a car left with positive caster the LF rises while the RF drops. This changes the weight on all 4 corners of the car. In effect you're taking cross weight out of the car the more you turn the wheel.

The more positive the caster, the more cross weight there is being removed. The more cross weight you remove the looser the car will get. Higher caster settings allow you to catch power slides on exit a little bit easier as well. Another element that must be considered is the caster split or caster stagger as I like to call it. Caster stagger is simply using different settings on the LF wheel than the RF.

When caster settings are different, your steering will tend to pull toward the side with the least amount of caster. On tracks where your only turning left, you would want a higher positive caster setting on the RF than the LF. This more positive caster on the RF will make the car pull to the left entering the turns, which is the preferred setup for entering the corners. The higher the caster stagger you run the easier the car will turn itself into the corner. Caster stagger will also affect braking.

If you run too much stagger at tracks that require heavy braking such as Martinsville or the road courses, you may have to add brake bias. Although a better trade-off would be just to even up the caster allowing you to brake harder without causing the car to pull to the side with the least amount of caster. Caster stagger is NOT the only adjustment that will give you that pull to the left. Many other factors must also be considered.

In other words, if you ran 1 degree positive on the LF, you would run positive 3 or 4 on the RF. Simulating the pull that a stock car gets in a game is going to yield different results for different types of controllers. To add to this variation, the Linearity setting you choose in setting up your controller, in combination with the steering ratio you choose within the setup is going to contribute in making the pull feel different from user to user.

Do you see real drivers using counter steering down the straights? No, because they can center the wheel on the steering shaft. Is the pull still there for them? You can get your controller to center on the straights by how you calibrate it, get rid of it entirely if you like.

Will you still feel the pull? No, why? Your controller isn't hooked up to the suspension of a stock car, so you're not going to be able to feel the dynamic pull that the suspension creates. Furthermore, your steering wheel doesn't have the range of motion as a real car. At best you're probably getting from to degrees of motion, and much less on a Joystick maybe 90 degrees if you're lucky? A real car has what, maybe 3 to 4 full rotations from lock to lock?

With this in mind the game has to have Steering Ratio values that can compensate for the lack of true lock-to-lock movement. The differences in degrees of lock to lock motion between a joystick and a wheel is why the Linearity setting makes such a big difference, it has to in order to make all types of controllers usable.

You just need to find the setting that is comfortable to you. Caster synopsis: More positive caster will loosen the chassis the more the wheel is turned through a corner. More positive caster will allow you to catch slides on exit a little easier.

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 easier the car will break loose braking 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 differential is a gear assembly in the rear end whose purpose is to distribute torque to the rear wheels for traction. It is always a good idea to clean your laptop screen or monitor before gaming. Learn how to clean a laptop screen or monitor safely with a few different alternative methods.

The ratio expresses the number of turns required by the pinion which is attached to the output shaft of the transmission to turn the drive axle one revolution, i. A higher number 6. 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.

We are allowed to choose from no less than 49 different ratios with an adjustment range from as low as 2. When you change the differential ratio, you change all the final drive ratios together proportionally. On short tracks you will want to choose a higher differential ratio because quicker acceleration will be a must at tracks where speeds are not as high.

At super speedways you'll want a smaller ratio for top speed since quick acceleration is not necessary on a track where you're at full throttle most of the time. The most important factor when considering what ratio to use is that you don't choose a ratio that is too high. Too high a differential ratio will result in running higher rpms.

If, by the time you reach the end of a straightaway, you're running higher than rpms. The rev limiter is used to prevent us from running too high an rpm, which could result in a blown engine.

You must watch your tach when changing gear ratios. If you're running too high an rpm you will also notice it through the sound of your engine as a "missing" sound. As you adjust other chassis components, you will most likely find yourself having to change your differential ratio. As you find more speed through the corners, you'll eventually find yourself on the throttle quicker.

Since you're on the throttle sooner you will be running a higher rpm towards the end of a straightaway. This is likely going to force you to make a differential change. Provides quicker acceleration, but slower top speeds. Provides slower acceleration, but higher top speeds. This is a non-adjustable option that is basically used for comparison purposes. The final drive ratio represents the number of engine revolutions to rear wheel revolutions.

The final drive ratios can be viewed for all four gears. A higher number means a lower or shorter gear. Your final drive ratio will be the same as your differential ratio. Front Bias The Front bias can be adjusted by clicking the weight bias tab on the garage screen.

Front bias is the amount of weight on the front of the chassis as compared to the rear of the chassis. Front bias is determined by placing lead weight at various points as low as possible in the chassis. Sliding this weight forward gives you more front weight or bias. The most front bias were allowed is The least amount is Generally speaking, the flatter the track, the more front bias required.

The higher the banking the less front bias required. This is because the higher banked tracks require less braking which in turn means less weight is being transferred to the front of the vehicle. Less front bias or more rear bias would be preferred at a track like Talladega. A slower track that requires shorter gear ratios, will also require less front bias.

This is due to the problem of wheel spin that can occur during acceleration. You would rather have less front bias or more rear bias to help transfer weight to the rear quicker to avoid wheel spin. Just the opposite would be true when a higher gear ratio is required. The less front bias you run the looser the chassis will be. Experimentation once again with all these variables will be the only way to correctly determine the proper front weight bias given the various circumstances.

Another factor that must be considered when dealing with front bias is Fuel. As fuel is burned, your rear weight distribution is lowered.

Although your not directly changing your front bias, you will be affecting the amount of weight that is being transferred as fuel is burned. This will result in an ever changing car as fuel dissipates. Front Bias synopsis: More front bias will tighten the chassis. Less front bias will loosen the chassis. Front Brake Bias Many people believe that the brakes in a racecar are used for nothing more than slowing or stopping the car.

Nothing could be further from the truth. Properly adjusted brakes can improve lap times by allowing you to get into a corner better.

Front brake bias allows us that same exact adjustment. Because of these varying factors more or less front brake needs to be "dialed" into the car. Since this will vary with each corner at each track, it is important to find the right balance as not to upset the chassis when you apply the brakes while cornering.

It is important not to confuse a loose or tight condition upon entry with a front brake bias problem IF your problem doesn't occur when using the brakes.

On the other hand, your chassis may not be tight or loose on entry, but because you have the incorrect front brake bias set into the chassis, you're creating a problem when using the brakes.

It is real easy to mask or create an I'll handling car getting into a corner by making a front brake bias adjustment. The more front brake bias higher the number you have set in the car the tighter the car will be on entry. The lower the number the looser the chassis will be. This tight or loose condition from front brake bias will only occur while your on the brakes entering the turn.

Some may try to add front brake bias to tighten up the chassis going in, but unless your using the brakes going in, changing front brake bias will be useless. Plus the fact remains that you are only masking the problem of the loose condition by trying to compensate with a brake adjustment. You might want to adjust the chassis elsewhere to tighten the car up on entry. So how do you know when you have the correct amount of front brake bias? I believe the correct brake bias is determined by how the chassis reacts when hitting the brakes hard going into a corner without locking them up.

It is important not to steer any more than is necessary. Any added steering inputs can throw off your results due to the added weight transfer that occurs while turning.

How did the chassis react? You ll probably also want to make sure that you re not using any caster stagger during this test. Once you have the brake bias the way you want it, you can go back and work on the compromise between caster stagger needed for turn-in but not so much it causes you to use to much front brake bias.

Front Brake Bias synopsis: 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 Roll Couple Whenever you turn, there is going to be some body roll.

Body roll has to be handled by the suspension system so the tires won t break traction. Since Cup cars use independent suspension, the front and rear of the chassis handle their share of body roll separately as it passes through the front and rear roll centers. Roll couple percentage is how much body roll is distributed between the front and the rear suspension systems.

Since we know the stiffest end of the car will slide first, roll couple provides a pretty good indication of whether the chassis is going to be loose or tight. If the front slides first, the chassis is tight and if the rear slides first the chassis is loose. Figuring out roll couple is a complex formula that includes roll rate, track width, spring rate, sway bar lengths and thickness, anti roll lever lengths and rates, and tire pressures.

Increasing the front springs and sway bars as well as decreasing the rear springs and sway bars will increase roll couple while doing exactly the opposite will decrease roll couple. The higher the front percentage number, the more under steer pushing there is in a chassis. Conversely, the less front roll couple, the more over steer loose. The reason the front roll couple percentage is so much higher than the rear roll couple is because most of the weight transfer from inside to outside during cornering should be led by the front or non driving wheels.

There is also a direct correlation of weight distribution and roll couple. Typically, as you move weight forward in the car, the less amount of front roll couple is needed. As you move weight back more front roll couple would be needed.

Adjusting roll couple should be done before adjusting wedge in regards to tightening or loosing the chassis. It is possible that taking out wedge could have a negative impact on right front tire wear as more dynamic weight may be distributed to the right front from the heavier load that was jacked static negative wedge to the left front and right rear.

Adjust roll couple before adjusting wedge to tighten or loosen the chassis. Front Sway Bar A sway bar is also known as an anti-roll bar or stabilizer bar. The purpose of a sway bar is to control body roll through a corner. This is done with a bar that connects to both front lower a frames.

Without getting to technical, a sway bar acts as a third spring to help balance out weight transfer during cornering. The sway bar is measured by the thickness or diameter of the bar. The thicker the bar the stiffer the bar. Here are the diameter choices of the bar: 0. Generally speaking, the larger the bar the less the body roll up front. The less the body roll the tighter the car becomes. Fine tuning with sway bars is an easy way to compensate for roll couple or body roll. Front Sway Bar synopsis: The larger the bar the tighter the chassis.

The smaller the bar the looser the chassis. Front Toe Out Front toe out is when the tires are farther apart in the front of the tire than the back. Toe in would be just the opposite.

Front toe out is utilized to help prevent tire scrub while cornering. Within the sim we are allowed adjustments that range from Under no circumstances would you want a toe in condition.

The majority of setups usually require a setting of less than 0. I wouldn't run anything less than. Larger radius tracks with long corners would require less toe out.

More toe out will help the front end stick entering a corner. A car will run faster with the toe straight. By monitoring tire temperatures you can tell if you have a toe problem with the chassis. Excessive toe out would show higher temperatures on the insides of both front tires. Excessive toe in would show higher temperatures in the outsides of both front tires. Front toe out isn't an adjustment that has to be changed or monitored as often as camber. Start with an adjustment of 0. Adjust the toe slightly only when the rest of the chassis is real close to being correct.

Fuel Level Your WC race car comes equipped with a 22 gallon fuel cell. Your allowed to adjust the fuels levels from 1 gallon to 22 gallons for practice sessions only.

All races as well as qualifying must begin with a full 22 gallons in the tank. Gone are the days of deciding how much fuel you want to add during a pit stop. We are now faced with 5 options. A splash of fuel will give you gallons. These options can be selected by hitting the left or right arrows on your keyboard after hitting F3. The less fuel your carrying the faster your car should be. This of course depends on tire condition.

The important thing to understand about fuel, is how it effects the handling of your car as it is burned. Multiply that times 22 gallons and you have an extra This is important to remember when taking on less fuel late in a race. If your setting your chassis based on using a full 22 gallons, you may think that by taking less fuel that you will be quicker. Depending on your setup that might not be the case. The best solution is to practice your setup with different fuel levels to see how it performs.

It's also possible to make a wedge or track bar adjustment in the pits to compensate for how your will react with less fuel. Fuel Level synopsis: Less fuel equals faster speeds. The less fuel in the tank the tighter the chassis will become. Grill tape is nothing more than duct tape. The only component were worried about is the radiator. The more tape you apply the hotter your engine will run. Running excessive amounts of tape for a long period of time will result in engine failure.

So why put any tape at all on the the front end? Instead of air going through the car, air is being forced around the car. This places more down force on the front end. More down force will make the front of the car turn into the corner quicker. Excessive amounts of tape can cause too much down force making the rear of the car lite creating a loose condition. Weather is another factor you must consider when deciding how much grill tape to use. It stands to reason the hotter the day, the higher your water temperature will be.

Therefore with the warmer weather you'll find yourself having to run less grill tape to allow more air flow through the front of the car. In other words, running the same amount of grill tape on the same track in 50 degree weather may cause an overheating or engine failure problem with the weather being 85 degrees.

Be sure to keep an eye on your gauges, or you may find yourself pitting to remove some of that tape. Try to get away with as much tape as possible on superspeedways without causing excessive water temperature. More tape will decrease lap times. If you discover you can get away with running more tape, but become to loose, adjust for the looseness elsewhere.

The hotter the weather the less tape you can use. Tape causes aerodynamic changes that have very little affect at speeds less than MPH. Left Bias The left bias can be adjusted by clicking the weight bias tab on the garage screen. Left bias simply means how much weight is on the left side of the car compared to the right side.

Between all the weight adjustments allowed, this one is the easiest to figure out. If you could run your car, with the weight being equal at all 4 corners entering a turn, then you would run faster than anyone else in the corners. With perfect weight distribution you would have perfect tire temperatures. Perfect tire temperatures equals the maximum traction you could attain.

This is what were all trying to accomplish with every single adjustment we make on a racecar. As heavy as WC cars are, left side bias on an oval is simple to deal with. Always keep as much weight as possible towards the left side of the chassis.

Whenever your dealing ONLY with left hand turns, always keep the left side weight at More left side weight allows you to take left hand turns at a higher speed. These obviously would be the road courses. Although at a track where there are more right hand turns than left, you may favor a higher right side percentage. This will allow you to get through those right handers a little more quickly, but at the sacrifice of losing speed going through the left handers.

This still could be advantageous if there are few more turns going right than left. Higher right side bias will cause the car to Under steer when making a left hand turn. Rear Sway Bar The purpose of the rear sway bar is the same as the front sway bar except it controls body roll at the rear of the car. The rear sway bar connects in the back between both rear lower trailing arms. As with the front sway bar, the rear is adjusted by changing the diameter of the bar.

The rear sway bar range of adjustments are as low as 0. This differs by a half inch over the front sway bar, yet the rear offers no less than 26 adjustments in 25 hundredth increments. The larger the bar the stiffer the rear becomes.

But by making the rear stiffer, it has just the opposite effect that occurs at the front. A larger rear sway bar will actually loosen the car up due to the fact that the way the weight is being transferred at the rear, is just the opposite of the the way the weight gets transferred at the front of the vehicle.

Rear Sway Bar synopsis: The larger the bar the looser the chassis. The smaller the bar the tighter the chassis. Ride Height The chassis ride height is simply the distance measured in inches from the bottom of the frame rails to the ground. This measurement is taken at all 4 corners of the car where the frame rails are lowest to the ground. Ride height is adjusted by turning down or up on load bolts located at each corner of the car on top of each spring.

Ideally you would want to run your chassis as low as possible. The lower your ride height, the lower your center of gravity. The lower the center of gravity, the lower the overall weight is to the ground.

The lower the weight the less weight transfer will occur while cornering. There are a number of criteria that must be considered when adjusting ride height. These adjustments are built into the chassis itself. Rear roll center can be taken care of by adjusting the track bar. Check you tire temperature for proper camber angles.

The most important factor we must consider is chassis clearance. If the ride height is set to low the car may bottom out on the track. This will more likely occur at high speed high banked tracks where the centrifugal forces are higher higher or at road courses where there are dips in the track.

If the car bottoms out in the rear you will most likely get loose. Bottoming out up front will result in a push. If you bottom out you can do one of two things. You can raise the ride height or run stiffer springs. Personally I've always believed that lower was better, but I also believe that softer springs are better.

Again, this theory depends on a lot of other adjustments set within the chassis, so experimentation is the only real answer. Lowering the ride height at those same corners will also lower the RF. The corner that is opposite is the LR. At the LF we are allowed to set the ride height as low as 4.

The higher the front of the car the tighter the car will be. The LR can also be set as low as 4. Adjusting the ride height effects the way weight is being transferred when cornering.

Running a higher LR ride height also puts more weight on the RR. This will cause a loose condition entering the corner. Another thing you must consider when raising the ride height in the rear is how it affects the aerodynamics of the car.

With that big spoiler running across the back, it will create more drag because it will be catching more wind. This will slow your straightaway speed. With more wind catching the spoiler it will also create more down force on the back of the car which should allow the back of the car to stick better in the corners.

Running a higher ride height may allow a lower spoiler setting. Springs will play an important rule in determining your overall ride height. In general, the lower the car, the faster the car should be, but possibly at the expense of bottoming out.

On larger tracks where moderate acceleration occurs at the mid portion of the corner, having the CG too far forward will result in a larger wheel steering angle in the corner and typically a push under steer exiting the corner. On short tracks where you have heavy acceleration, having a CG too far forward can result in rear wheel spin and a car that feels loose overseer when trying to exit the corners. The higher the CG is above the ground the more weight will transfer to the outside tires in a corner.

A higher CG can also exaggerate the affects of Tip E below. Raising or lowering the CG can impact suspension geometry such as rear axle steer or camber gain in the front suspension. Let the front roll center fall where it may in order for the front suspension to have good camber curves. Use the rear roll center to tune your race car's handling. Elevating the rear roll center tends to make the car looser overseer in the mid portion of the corner when the centrifugal force is highest.

Many people refer to this parameter as roll couple distribution. There are no fixed numbers for this parameter. Your settings back at tip A will affect your ideal numbers. Anybody can crank on the weight jacks until the race car has balanced handling. Cross weight preload is a way of measuring how efficiently the car is balanced. After you make the spring change it will be necessary to readjust your corner weights. Typically for pavement tracks the front has a larger number.

Dirt tracks typically require a larger number at the rear. In all cases, changes that decrease the rear number make the car tighter and increasing the rear number makes the car looser in the turns. While weight jacking is a quick and simple way to change the handling of the race car, it is still a crutch.

Follow instructions in the manual on how to interpret the preload and determine what the race car wants for springs. Before your race car goes on the track or at the shop the tires are "Cold. As soon as you stop the tires are still "Hot. This measurement can change from cold to hot conditions just like the pressure.

A computer is just dumb box. It only know what you tell it. For example, if you were to race your car and have the right front brake rotor glowing bright red you would see this and would be registered in your brain. The computer can not see t he car and does not know that a large heat source is near the wheel and tire.

The temperature of a wheel can be elevated to the point where more heat is reaching the air inside the tire from the hot rim than is coming from the tread surface of the tire. If the software were to read only the tire temperatures it may suspect a slightly high air pressure, but with the rim temperature the software would know about the heat coming from the brake rotor.

A good place to take the rim temperature is where the center flange of the wheel meets the rim portion of the wheel. Ride Height synopsis: 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. 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. These notes could be useful for setups at tracks with familiar configurations which can turn out to be a real time saver.

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. 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.

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. 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.

A shock controls the speed at which the spring moves. 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.

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. The compression of a shock is when it is being pressed down. The rebound is when it is being pulled back up. This means that the shock when compressed, has the same resistance when pulled apart. This shock would be stiff to compress, but would rebound or pull apart real easy.

By adjusting the valving of each shock you can fine tune your chassis through a corner. 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.

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. 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? What are the shocks going through in this state? Generally speaking, this is the exact same thing that occurs in a racecar upon entering the corner. 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 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.

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.

Consequently, the left side tires remain loaded further into the corner which helps to turn the chassis. 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. 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.

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. 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. Say 9 compression 9 rebound, or 1 compression 1 rebound.

Once again I bring up stiffer equals less grip on that corner. 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. The RF is still stiffer. 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. 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. 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. 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. 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. 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. Overall stiffer LF shock will loosen chassis, weaker will tighten it. LR Higher compression will loosen the chassis accelerating out of 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. 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.

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. The lower the number the straighter the spoiler or the less down force there will be on the rear of the car.

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.

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 mph over the length of the rear deck lid will be a lot higher than your hand out a window.

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. The front springs are adjustable in 50 lb. The rear springs can be adjusted as low as 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. 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. Running more spring stagger up front, with a weaker left side spring, will tighten the car under acceleration while loosening it under braking. 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. A stiffer RF spring will make the car tighter. 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. All will help to tighten the chassis.

I remember all this by simply knowing that a stiffer RF spring equals a tighter race car. 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. Steering ratio is measured by dividing the number of degrees the tire is turned into the number of degrees the steering wheel is turned. The lower the ratio 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 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 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 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. 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 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.

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. 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. Luckily, the motorsport specialists at Team O'Neil Rally School up in New Hampshire put together a comprehensive video explaining every aspect of a car's suspension, what each part does, and how adjusting it can affect your car's performance. Wyatt Knox of Team O'Neil goes over things like spring rates, ride height, shock compression, rebound, alignment, and tire pressure, making sure to explain how each piece of the puzzle fits in.

He even explains how a rally setup would differ from a road racing one. The video might be a bit lengthy, but we have a feeling you won't regret sticking around. And if you have an adjustable suspension, it's a must-watch. Join Now. New Cars. Car Culture. Type keyword s to search. Today's Top Stories.