tcmc5

I'm hoping some of you racers( T1ers, Lou G, Dave F) might comment. Will changing the rake of the car allow me to change oversteer, understeer
or braking behavior of my car? Any rules of thumb? On my car, rear is 1" higher than front and handling is tending toward oversteer with 315s front and rear. Thanks.

Guest

Lowering the rear reduces the oversteer tendency on corner entry and transitions it seems, so you could try removing about 1/4" at a time. A 1" change is very noticeable, even at low speeds.

Paras

Does the back of the car seem more stable if it the rake is more neutral?

z060ntrack

Let's look at it this way, lower the front or raise the back to decrease understeer. So to deal with oversteer do just the opposite.and always do in small increments until you get the desired result. C5's need a little rake, a level car is going to understeer.

davidfarmer

having the front lower increases overall downforce (or reduces lift on a stock body). I suggest starting with the nose down up-to 1" (measure along the frame rails, just behing the front tires and ahead of the rear). If you have oversteer, lower the rear bit by bit. If the car pushes or is neutral, leave it alone.

Dave

tcmc5

Thanks a lot guys. Just the kind of info I was looking for. Think I'll try reducing rake a little and see if it corrects my slight oversteer.

Bill Dearborn

How experienced are you? You might do better changing your driving style. If the car is tightening up on you as you go through a turn you may want to add more throttle. This will transfer more weight from the front to the rear and counteract the oversteer.
Bill

TheDarkKnight

ok related question. What kind of change is to be expected by making no other rake-like changes than moving to the same diameter wheel/tire on all fours? I ask because I've got 4 305/30/18s awaiting their first autocross event.

Gordy M

From the factory, you come with a 1/2" rake measured at the wheel centerlines and 0.22 in rake measured at the jack points. GM does this by wheel size and then has a series of measuring points for ride height. The faster your speeds, the more you need either a wing or rake. For autocrossing, most of the top tier cars have 1" or more rake. Remember, most of them do not drive their corvettes on the street.

corvette dave

tcm,
The wider tires in front probably added more grip there and contributed to the oversteer.
Also, the amount of fuel in the tank can have an affect on handling.
A full tank should decrease oversteer a little.
What type of events are you doing with the car?

Dave

TedDBere

Seems to me I remember Danny Poppa being quoted as running 1/2 inch rake. Anybody remember reading this?