F-Body Europe

I was searching for some info on suspension tuning to write an article and low and behold one of our members did it back in 2000-2001. Thanx man.

By STEF SCHEEPERS

If you have to ask "what is understeer / oversteer?", it’s quite simple: if you approach a fast bend in the road, turn the wheel, but the car just plough straight on into a ditch, then you suffer from understeer. If you leave the same bend spinning backwards into the ditch, then you suffer from oversteer. Of course oversteer can easily be provoked when there is an idiot at the wheel, so don’t always blame the car.

For those of you who understand your car’s dynamics well enough not to make the typical beginner’s mistakes that will upset the handling, here is a list of changes that will guide you to tune your suspension to a neutral-steer for superior high-performance handling.

DECREASE UNDERSTEER..... CORRECTION.....DECREASE OVERSTEER

higher pressure........................tire pressure - front......................lower pressure

larger contact area....................tire section - front...............smaller contact area

more negative.........................wheel camber - front.......................more positive

softer............................................springs - front.........................................stiffer

thinner (softer).............................sway bar - front.........................thicker (stiffer)

larger...........................................spoiler - front.......................................smaller

lower pressure.........................tire pressure - rear.....................higher pressure

smaller contact area.................tire section - rear..................larger contact area

more positive.........................wheel camber - rear......................more negative

stiffer............................................springs - rear.........................................softer

thicker (stiffer).............................sway bar - rear.........................thinner (softer)

smaller..........................................spoiler - rear........................................larger

weight bias rearward................weight distribution..............weight bias forward

A few words of warning: if you are unsure about what you are doing, rather get help from an experienced person. Make your changes in small increments and first test the result in an open area where you can do little harm (like at one of our slaloms). Rather tune towards neutral-understeer, since an oversteering car is quite a dangerous beast that needs a fast hand to catch it. Have fun.

Nobody can say Stef would avoid clear statements Love it ...

Once again GREAT info!!! Thanks Roy & Stef

Aaahh, glad to see that somebody occasionally read the stuff that I write.

Well, usually you're busting people's balls. So, you have to excuse most of us

I don't geddit?

one more thing to add to that: Rake (difference in the ride hight at the front of the car and at the rear of the car). on a Corvette, the factory says 1/2" when you measure it at the center of the wheels, not sure about the F-bodies

too much rake will cause your car to oversteer, and to little will cause it to understeer.

when I 1st lowered my car, I pulled the nose down more than the rear and it was a hand full until i figured out what was wrong. problem when away as soon as I pulled the rear down another 1/4" That also affects the high speed aerodynamics of the car, the angle of the body helps create downforce and keeps the car stable. 99% of the guys that say their vette is not stable at high speed have lowered the back of their car too much (the C5 has can more room to adjust the hight at the rear than the front)

Stef,
I think Jason was just playing with you, I know that I can use as much good info as I can get. Everylit little bit helps to get closer to that perfect setup....if there is such a thing.