Welcome, Last Update: Mar 26, 2018

From Lou Olesky (part 3)

Left Front Checklist:

Corner Weight: This is the weight of the left front as it would show if the car were on a scale. Increasing this number helps the car turn. Always keep an eye on corner weight, this is what lets you know if your cars going to turn well through center.

Ride height: This is the height of the left-front corner of the car's chassis. Raising this will likely result in a lack of grip at the front of the car.

Shock collar offset: This is the measurement from the shock collar to the lower end of the shock body. Increasing this measurement will lower the ride height and tighten the car up. Decreasing this measurement will have the opposite effect.

Spring Rate: This is the rate of the left-front spring. Increasing this will help the car turn and lowering will tighten the car up (move the handling balance toward UNDERSTEER).

Camber: This is the adjustable angle (left to right) of the tire to ensure you have the maximum amount of tire on the ground while cornering. On ovals, where the car is always turning left, this setting will be in the positive numbers, so that as the car rolls in the turn, the tire stands up and generates maximum grip. Note* Too much camber can overheat the tires outer edge and in the end result in loss of grip.

Caster: This is the adjustable angle of the spindle (front to rear) which allows the left front tire to be forced into the race track surface. Most oval cars maintain somewhere around a two-degree split in caster left to right. The left will typically have a lower caster setting than the right. Less caster in the left front will help the car turn left, particularly from corner entrance through the center of the corner. Closing the split between left and right will tighten the car, while increasing the split will loosen it.




The following comes from Lou Olesky. It is his hope that this will benefit some of you.

**Note**
The first HUGE part of this is not mine. It's something I found on the web ages ago, and I have it saved to a word doc, I don't remember where i got it, or who the original author is. The 2nd part "Short checklist" is what I do to get a base setup for all my cars "except legends".

Tire Pressures: Changing tire pressures is probably the most powerful adjustment available as tire performance affects every part of a lap.

Ideal tire pressure is determined by the load the tire carries – higher pressures handle higher loads better. That is, in a heavier car, or a banked turn, or compression at the base of a hill, more grip will be retained with higher pressures, whereas with lighter loads, lower pressures tend to give better grip.

Increasing the pressure will in effect STIFFEN the sidewall of the tire, which makes the tire more responsive to the driver’s inputs, particularly during the initial turn-in for a corner. The compromise is that as the tire becomes stiffer it will start to lose compliance with the road. Therefore, bumps, curbs and violent inputs from the driver may result in a loss of traction.

Decreasing tire pressure will SOFTEN the sidewall of the tire. As the tire softens, the compliance improves and, generally, grip improves. The downside is that the car will become less responsive to driver inputs, (i.e., the car feels sluggish).

Cold Pressure: A measurement of inflation pressure (measured in “psi” – pounds per square inch) when the tire is at ambient temperature in the pits, before having been run on the race track.

Last Hot Pressure: This is the tire pressure as recorded when you exit your car, or pull into your pit stall, whichever is first. As tire temperature increases in a run, so does the pressure in the tire. Generally, this pressure will stabilize after a few laps.

Last Temps O M I: This is the tire temperature as recorded when you exit your car, or pull into your pit stall, whichever is first. At the end of a run the surface tire temperatures are displayed with readings taken at the outer edge (O), middle (M) and inner edge (I). Generally speaking, these readings hint at how well the tire is being maximized. A good rule of thumb is that the temperature differential should be about 10 degrees (+/- 5) from the outer to inner edge of the tire, with the inner edge being the hottest.

Front setup checklist

Toe-in: Toe-in will help your car turn, particularly at exit of the corner. Reducing toe-in (or going to toe-out) will make the car tighter and noticeably more stable on exit of the corner.

Sway Bar: A smaller sway bar will cause the car to roll more to the outside in corners. The result is that the car will tend to be “looser” (handling shifts toward OVERsteer) as the right front travels and takes weight off the left-rear of the car. Sway bar settings are mostly driver preference. There is no wrong answer or sweet spot. When you like the car’s attitude mid- corner the sway bar is doing its job. Changing the sway bar diameter gives bigger changes in bar stiffness. For finer adjustment, use the sway bar arms (see below.)

Sway bar Arm Length: The sway bar arm length can be adjusted in three settings: 14”, 15”, and 16”. This arm is connected from the sway bar itself directly to the lower “A” frame on both the right- and left-front suspension, one arm for each side. Changing the arm length fine-tunes the stiffness of the sway bar.

A shorter arm will enhance the sway bar’s effect on cornering. A longer arm will lessen the sway bar’s effects. Shorter arms will tighten the car up. This increases the bar’s effective stiffness by reducing the length of the lever-arm through which the wheel acts on the bar. A longer arm will soften the sway bar and allow the car to turn better. The effects of the sway-bar-arm changes will mostly be felt on entrance and exit of the corner, and less so during steady-state cornering.

Left Front Checklist -

Corner weight: This is the weight of the left front as it would show if the car were on a scale. Increasing this number helps the car turn. Always keep an eye on corner weight, this is what lets you know if your cars going to turn well through center.

Ride height: This is the height of the left-front corner of the car’s chassis. Raising this will likely result in a lack of grip; lowering it will increase grip at the front of the car.

Shock-collar offset: This is the measurement from the shock collar to the lower end of the shock body. Increasing this measurement will lower the ride height and tighten the car up. Decreasing this measurement will have the opposite effect.

Spring Rate: This is the rate of the left-front spring. Increasing this will help the car turn and lowering the spring rate will tighten the car up (move the handling balance toward UNDERsteer.)

Camber: This is the adjustable angle (left to right) of the tire to ensure you have the maximum amount of tire on the ground while cornering. On ovals, where the car is always turning left, this setting will be in the positive numbers, so that as the car rolls in the turn, the tire stands up and generates maximum grip. Note that too much camber can overheat the tire’s outer edge and in the end result in loss of grip.

Caster: This is the adjustable angle of the spindle (front to rear), which allows the left-front tire to be forced into the race track surface. Most oval cars maintain somewhere around a two-degree split in caster left to right. The left will typically have a lower caster setting than the right. Less caster in the left front will help the car turn, particularly from corner entrance through the center of the corner. Closing the split between left and right will tighten the car, while increasing the split will loosen it.

Right Rear Checklist-

Corner weight: This is the weight of the right rear as it would show on a scale. Increasing right-rear corner weight helps the car turn.

Ride height: This is the height of the right-rear corner of the car’s chassis. Raising the ride height will reduce rear grip.

Shock-collar offset: This is the measurement from the shock collar to the lower end of the shock body. Increasing shock-collar offset raises the ride height and tightens the car (changes the handling balance toward understeer.) Decreasing the offset has the opposite effect.

Spring Rate: This is the rate of the right-rear spring. Increasing the spring rate helps the car turn, while lowering it has the opposite effect.

Shock Stiffness: Shock stiffness is the measure of how much force is required to compress the shock. This setting works much like the springs themselves. Changes in shock stiffness affect the car much less than increasing spring-rate by 50 or 100 pounds, which means that shock adjustment can be a good way to dial the car in. A stiffer shock on the right-front or left-rear will increase the dynamic wedge while cornering and make the car more stable and less likely to rotate. A stiffer shock on the right-rear or left-front of the car will decrease the dynamic wedge while cornering and allow the car to rotate more.

Right Front Checklist

Corner Weight: This is the weight of the right front as it would show on a scale. Increasing this number tightens the car
Ride Height: This is the height of the right-front corner of the car’s chassis. Raising the right-front ride height can increase front grip if the right-front tire is being overloaded, resulting in an adverse camber effect. Optimum ride height can vary greatly depending on other chassis settings and the degree of banking at a particular track.
Shock-collar Offset: This is the measurement from the shock collar to the lower end of the shock body. Increasing right-front shock-collar offset lowers the ride height and helps the car turn. Decreasing shock-collar offset will have the opposite effect.
Spring Rate: This is the rate of the right-front spring. Increasing the right-front spring rate tightens the car, while lowering it has the opposite effect.
Camber: This is the adjustable angle (left to right) of the tire to ensure you have the maximum amount of tire on the ground while cornering. On ovals the right-front tire should be negative, so that as the car rolls in the turn, the tire stands up and produces maximum grip. Too much camber overheats the tire’s inner edge, which reduces the tire’s total grip.

Caster: This is the adjustable angle of the spindle (front to rear), which allows the right- front tire to be forced into the race track surface. Most oval cars require approximately a two-degree split in caster left to right, with the left front running a lower caster setting than the right. Less caster in the right-front will help the car turn, particularly from the entrance to the turn through the center. Closing the split between left and right will make the car more stable and possibly tighter.

Left Rear checklist:

Corner Weight: This is the weight of the left rear as it would show on a weight scale. Increasing left-rear corner weight tightens the car (changes the handling balance toward UNDERsteer.)

Ride Height: This is the height of the left-rear corner of the car’s chassis. Adjusted in isolation, changes to ride height will affect cross weight. See Shock-collar Offset for more info about changing the ride height.
Shock-collar Offset: This is the measurement from the shock collar to the lower end of the shock body. Increasing left-rear shock-collar offset lowers the ride height and helps the car turn. Decreasing left-rear shock-collar offset will move the handling balance toward UNDERsteer. Spring Rate: This is the rate of the left-rear spring. Increasing the rate of this spring will tighten the car, while lowering the spring rate will move the handling balance toward oversteer.

My step by step process for my base build

1- Tire pressure
2- Camber
3- Caster
4- Back to tire pressure, I do this to adjust how I want my car to feel.
5- Fine tune camber and caster
6- Rear end ratio “I like to hit my rev limiter just before my brake point”
7- TOE in/out depending on how you want the car to feel going into turns
8- Brake Bias
9- Preliminary ride heights
10- Springs
11- Adjust ride heights again, “Keep an eye on corner weights”
12- Sway bar length and stiffness
13- Adjust springs again if needed
14- Adjust ride heights again if needed
15- Bump and rebound stiffness

Everything else after this will be fine tuning. But this should get you a solid base setup.




Doesn't matter if your tweaking an iRacing set or a base set that someone else has built. Most times the set isn't going to fit your driving style and the feel you like perfectly. Everyone who participates in open setup racing should know some basics when it comes to tweaking sets.

Now everyone should know that adding tape will loosen a set up the majority of the time. The exception would be if the front splitter or suspension is hitting the track in which case it will make the set more "pushy". Watch the replay when you come off the track, if it doesn't look like the splitter or side rails are disappearing into the track, add tape. Add as much as you can but you until your Oil/Water temps hit around 270 degrees.

The second thing I want to mention is ride heights and spring perches. If your splitter or front of side rails are disappearing into the track, or if your seeing sparks continuously coming out of the rear of the car, you need a ride height adjustment. Determine is you want to raise front, right, left or rear of car. Now whatever end or side of car you want to raise, left click both of those spring perches equally. Try 1 click on both and test, try a 2nd click on both and test, etc. Additionally, when you lift a side it will effect the preload on your roll bars. When you click 3 times on both perches on 1 side, you need to click once on preload to bring it back where it was. This will further raise or lower the car in the direction you are going.

While we're on the subject of spring perches let me tell you how they work and a second way to use them. A spring perch is a round pad that sits on top of the coil spring. In the center is a threaded rod or bolt that extends up through the frame with a top that can be adjusted with a wrench. When you screw down on it, it compresses the spring and raises the body off that spring perch simultaneously. Which brings us to the second use for the spring perches and that is to adjust crosswieght. By screwing down on the left front and/or the right rear, this stiffens those corners. This makes the tire heat and wear on those two corners increase. This is a way to loosen the car, especially center and exit. Softening will have the opposite effect. The opposite is true with the right front and left rear. Screwing those perches down will increase the crosswieght and tighten the car. Just remember opposite corners. Which do you want to do? Again, this effects ride heights. If you want to lower the left front splitter and loosen the car, screwing down on the right rear would work, because screwing down on the left front will raise the splitter further.

Now if a set feels loose or tight another area to start would be your rear track bars. Raising track bar heights stiffens rear suspension and therefore loosens car. Raising both sides loosens entry, center and exit. Raising just the right tends loosen exit more, while adding left will loosen entry more. The max split between the left and right is 3 or 4 inches depending on the vehicle. And naturally, lowering the heights will tighten.

Another place you can loosen or tighten a car is with camber. Increasing that left front camber can really loosen a car on exit. Increasing the right front camber can make you better in, but be careful with your right front, it's your most important tire on your car. Burn the inside off with too much camber and you'll be pushing real quick. There are other ways to tweak too. Save those for another day.

When Nascar teams get ready to go to the track, they leave their shops with a "BASE" set. They try to anticipate what the weather, temp and track conditions are and make their best guess as to what to put in the car. But the cars are never perfect when they get there and they need to adjust. This ability to adjust will determine more of who wins than what came out of the truck in the first place. Master the art of tweaking a set during that one hour practice! In the end, when your on the track, your basically down to only one adjustment. That's the rear spring perches. You need this to compensate for the changing track conditions. When rubber is building and the track is making you tighter, left clicking that right rear spring perch will loosen you!




Stiffer front bump = more under steer on corner entry
Softer front bump = more over steer on corner entry

Stiffer rear bump = more over steer on corner exit
Softer rear bump = more under steer on corner exit

Stiffer front rebound = more over steer on corner exit
Softer front rebound = more under steer on corner exit

Stiffer rear rebound = more under steer on corner entry
Softer rear rebound = more over steer on corner entry

Springs hold up the car and dampers control the springs loading and unloading. The springs react to movements such as bumps and road irregularities, it's actually the springs that dampen the roads surface it's the dampers that control the timing of the springs movement.

You have the compression cycle of a spring or bump and the extension cycle of a spring which is rebound.

Imagine a car without dampers and just springs, if you went over a bump in the road the spring would absorb the bump in compression but continue to oscillate or move up and down (Compression and Extension) until the spring calmed down. Add dampers to the springs now you can control this oscillation or movement of the spring.

Without a damper a spring will release it's energy from bumps in the track or kerbs say at an uncontrollable rate, dampers control the springs rate of movement or timing....Really this simple, fine adjustment of how the spring works.

Go over a kerb and you experience a compression of the spring and the damper is now in compression or bump phase, it's going up into the wheel well, the damper is controlling the speed this spring compresses. The flip side of this is now the spring wants to release all that squished up energy and at a pretty violent rate and this is where rebound comes in, rebound damping controls the speed the spring is released.

EXPERIMENT: Take a spring from a pen, it's really easy to compress but it sure wants to release all that energy in a hurry, you can use your two fingers and a spring from a pen to simulate how a spring and damping works, the speed you allow the spring to compress and extend is similar to controlling damping.

How does all this fit into what i need to do to make damper changes ? That is the question race fans, i know what dampers do but what do i do with them, it's a popular question so don't worry about it.

Um so you go into a right-hand corner, whoosh all the weight transfer goes to the left front and compresses the left front spring but also extends the right rear spring. Left front spring is in bump mode and right rear in rebound mode. As you reach apex off throttle the weight transfers off the left front a little to the left rear putting left rear in compression or bump and putting the left front into extension or rebound and right front into more rebound, the right rear kinda hovers there in rebound.

As you get on the gas more weight is transferred from the left front to the left rear this would be rebound in the front damper and bump in the left rear damper. The weight transfer keeps moving anti-clockwise until you are accelerating straight and all the weight transfer is at the rear under compression and at rebound at the front.

What your doing with dampers is controlling this movement or timing of the springs compression and extension as it cycles through the weight transfer from the car braking, cornering and accelerating, they also control what the car does in a straight line or what the springs are doing in a straight line, basically anytime the springs move the damper is in charge of how fast or slow it compresses and extends.

It now gets complicated because if other settings on the car are wrong like springs rates you can be chasing damper settings forever, you really have to make sure the rest of the car is setup, dampers are a fine tune of the springs oscillations, if you don't have the car setup then it's tricky to talk dampers because you are unsure if the rest of the car is correct. I would advise to work on dampers last in testing, if you do a spring change you affect the dampers and have to reset them again for the new spring rates, very annoying.

Just to point out dampers do not need to be the same or symmetrical values each side, they can be asymmetrical or all completely different even on the road side. I often run with just wacky numbers in the damper settings, camber settings, even spring settings i can have all four springs at different rates at a road course, who says they need to be the same front to rear











In Windows' Game Controllers settings:
Rotation: 900 degrees
Enable Force Feedback: Check
Overall: 70%
Spring: 40%
Damper: 40%
Enable Center Spring: Check
Center Spring: 50%
Allow Game to Adjust: Check

In-Game Settings:
Rotation: 900 degrees
Brake Force Curve: 0
Force Feedback Strength: 18
Damping: 0



These setting may vary from driver to driver