Slightly tailhappy... Options

[falcor75]

I need to learn a bit of how to setup my car better.
Its got new Bilstein shocks all around, new bushings everywhere.
Front has the stock torsion bars and a Tarret adjustable swaybar.
Rear has 140lbs Weltmeister springs.

Last year I ran it with no rear swaybar and the front swaybar set at about 25% from the outer most position. This got the car quite tailhappy when doing autocross/slalom events.

During the Winter I added the stock rear swaybar just to see what difference it made and it calmed the tailhappyness down a bit but still a bit twitchy.

Whats the next step? Decreaseing the front swaybar setting?


Last year in the wet..
https://www.youtube.com/watch?v=yrh878om6pI

This years first event
https://www.youtube.com/watch?v=Eer4JyMl_PI

[PlaysWithCars]

Adding more roll stiffness in the rear should have made it MORE tail happy, not less. Generally you need to soften the end that is loose or tighten the end that is planted in order to get the car balanced.

Have you checked your alignment? It can have a significant impact on handling as well.

[falcor75]

I had it aligned last spring.
front and rear 1,2 degrees of camber,
slightly toe out front and 2 mm toe in rear.

[gereed75]

Mat, Car sounds great and looks great too. Looks fairly neutral in second vid. Not stepping out even during trailing throttle turn in.

Yep, bar in back should increase oversteer.

what rear tire pressures were you running?? Good pressures are surprisingly low - in the 22-26 psi range.

[falcor75]

I'm running 1.8 bar or 26 psi all around, 195/55-15 tires on 7" rims.

[ConeDodger]

In a fairly tuned suspension, I’d make adjustments with tire pressure. 1psi out of the rear.
Your car should step out in the wet. It’s as if you added 700 HP or were driving 20 MPH faster.
You can’t compare the two situations. Only same day, same tire same course.

[falcor75]

In a fairly tuned suspension, I’d make adjustments with tire pressure. 1psi out of the rear.
Your car should step out in the wet. It’s as if you added 700 HP or were driving 20 MPH faster.
You can’t compare the two situations. Only same day, same tire same course.

I did autocross it in the dry last summer too its just that I only had the video of the rainy event. (IMG:style_emoticons/default/smile.gif)

[PlaysWithCars]

(IMG:style_emoticons/default/agree.gif) Once dialed in, small changes should be able to be made w/ tire pressure adjustment. But, it doesn't sound like you're at the point of 'dialed in' quite yet.

What size bar are you running in the front? 140lb rear springs, no rear bar, stock torsion bars and a 19mm front bar is a good combination. You should be able to run the front bar at mid- to full- stiff (drop link adjusted closest to the sway bar) to relieve your over steer.

My experience w/ a reasonably stock car was using stock rear springs, a stock rear sway bar, stock front torsions and a 19mm Weltmeister front sway bar (set up for SCCA stock class). With this set up my default tire pressure was 26psi front / 29psi rear.

[falcor75]

I think its the 19 mm adjustable Tarret front sway bar I have. But I have it set at around 25% from the softest setting (furthest away from the ar istself)

[PlaysWithCars]

To correct an oversteer condition, try stiffening the front bar.

[falcor75]

Ok, I need to get under the car soon anyway so I'll stiffen the front to the middle setting and report back. (IMG:style_emoticons/default/smile.gif)

[jmitro]

is it tail happy in tight turns or wide sweepers?

Its been 20 years since I autox'd but I'd guess you want it slightly tail happy to get around the tight corners quickly

[Racer]

Driver style plays into this as well. I prefer oversteer in AX events to help rotate the car around tighter gates. Then I just learn to keep the gas down all the time.