In czech league we're now racing FXO's (with skins which mimic Skoda Octavia ). Firstly I decided to do my own setup. It was fairly conventional one, balanced springs, strong rear sway bar and some toe-out to reduce the dreadful power-understeer. I was like 2 percents slower than the guys. Eventually I gave up and tried their settings. Few corners I didn't see the way, how it could be so fast, but then i realized it was giving me OVERSTEER while on gas (to some extent, i mean until the turbo kicked in). Now I would beg some physics & setups guru to explain me, how it works (attaching *.set now), my non-sophisticcated quess would be, it has something to do either with dampers, or the "it's so tight it's loose" phenomenon.....

I cannot look at it ATM, but I'm guessing:

Rear toe out?
Soft rear tyres?
Relatively high power-locking, or locked?
Strong rear sway bar?


I have the same behaviour (oversteer on power) on my Stunt/Rallye setup, and IIRC these are the main things I changed.

OK some points of interest:
* Brake-bias is back far enough to lock the rear wheels under normal braking, this obviously will create oversteer if you trail brake.
* The locked diff creates loads of understeer at low speeds, applying power reduces this understeer but does not create oversteer, although the feeling of increased turn in is the same.
* The rear tyre pressures are a bit high with those fronts, hence the oversteer that can be acheived during corner at higher speeds (mainly on corner entry... more on that later)
* The springs are setup to give lots of understeer, with a reasonable rear suspension frequency but a very high front frequency.
* The anti-roll bars mimmick this, being stiffer at the front... not helping the low speed understeer at all.
* And the worst bit: damping. With the exception of front compression (bump) damping, the dampers are set between too high and way too high. Hence the awful handling over bumps and general shaky feel.
* Finally looking at the dampers affects on transients, they give lots of oversteer on throttle lift (helps make the car driveable with the throttle), some oversteer when trail braking (works in tandem with that brake bias), oversteer on corner entry and finally understeer on corner exit.

In short it's one of the worst setups I've seen. Although I can't argue if it can achieve good times (camber is set well... )

Indeed Bob, it is one of the worst setups I've seen too. Therefore I needed some explanation, why it handles how it does. Anyways, would it be possible to archieve same handling characteristics with reasonable settings? Would this reasonable set reach same grip levels?
Then one OT question for guru's again: "What's the difference between spring rate and wheel rate?" Has it something to do with stiffness of wheels (AFAIK they should act as spring too) added to the springs?
If I knew exact stiffness of a spring in a real car, it would be spring rate and I had to do some calculations to determine wheel rate and only now I could feed LFS with these data, right? (speaking mostly about tweaks now)

btw. thank for your response Bob

I'm not totally sure myself, but ignoring tyre flex for now you get at least two frequencies from the springs along. The first is what we would normally look at, which is when you hold the wheels and the car body moves about. But you'll also get a (typically much higher frequency) if you hold the car body and move the wheels.

I believe this is where 4 way adjustable dampers become useful, as during a "fast bump" situation (eg. curbs) only the wheel really moves, whereas during a "slow bump" (e.g. the bump in old blackwood straight) the whole car body is moving. Due to the reduced weight you would want less damping under fast situations (and they also help improving ride quality).

It is not new that FWD have now oversteer on throttle, lots of people do not want to admit it, but it is true : they handle like a 4WD illepall , and they have more traction than RWD