DaveL82

Over the last 2 years I've been building my old 80 C3 as a track day, open road race and road ralley car. I've owned the car for 22 years and over the last 2 have made significant mods to bring it up to an acceptable level and yes I know it's better to buy a newer car already done but building it has been a very good experienece since I could see it taking place very daily, had to learn to weld and a good excuse to buy cool tools.

The car has a VBP front transverse spring kit with carrera shocks. The rear has QA1 coil overs (5 clicks from zero) using 350lb springs using my own mounting assy that will be modified later for toe link control. Car runs on 17" x 10" 275/40 ZR17 fronts and 18" x 12" 295/35 ZR18 rears (CCW wheels and Kuhmo MX tires) with flares. Front brakes are currently Wilwood Superlites however running stock rotors for now with Hydraboost).

Also have an AutoPower roll bar, OMP seats, ZZ4 engine, Richmond 5 speed with hydraulic clutch (was originally an automatic).

Here is the situation:

I believe the VBP front transverse spring also acts as a sway bar since the spring pivots on the arm arm mounting points. This was noticed when I put the kit on 10 years with no other changes, the car was very flat through the corners.

Now that I've updated the rest of the old beast I had friend of mine who is a track day instructor try out the car. He said he was very surprise by how the tight the car feels, it's very quick and turns very well. The issue is at high speed and letting off the gas in a slight cover uncovers over steer. He was able to apply power to bring it back under control.

My question is that with no swaybar in the rear I can't reduce that so would reducing the stock 1 1/8" front bar possibly help. I do believe after a few track days which the car seems ready for and I might be able to learn to control it however my wife wants to drive it as well, so I want to make it more neutral or possibly understeer for her.

Dave in TX

davidfarmer

if anything, you'd want to stiften the front. You always want to (relatively speaking) soften the loose end.

If the car is neutral at all other times except the one expeption you notes, than you might be stuck. However, if it really bothers you, soften up the shocks in the back, and see if anything happens. Also, alignment and tire pressure can make a big difference in drivability, even sacrificing a little grip in the front for overall control.

DaveL82

David - Thanks for your help and yes you're correct I was going the wrong direction with the front bar. I may try to incorporate an adjustable race type bar for the front.

Gordy M

When I was running my C2, I found that 2 1/2 deg camber front and back solved most of my throttle power over steer problems and corner weighing solved most of the remainder. Also, I ran with a large amount of rake to keep the front in planted at speed. (Not much of a problem with C3).

Solofast

David is correct, this is a transient response and is best addressed with shocks, soften the rear rebound or stiffen the front jounce and that will straighten it out.

RAFTRACER

In my C3 studies, I have found that BIG front spring rate, alot of front roll coupling, front bumpsteer study ( better be running some static toe-in), and very little or no rear sway bar works best.