The car is loose! help

[RR]

Practice yesterday with newly build rear wheel drive car. In tight cornering I could not get the hammer down, car kept oversteering bigtime. Any thoughts.

[Blix]

Originally posted by RR:
Practice yesterday with newly build rear wheel drive car. In tight cornering I could not get the hammer down, car kept oversteering bigtime. Any thoughts.

Start with the basics. Everything setup the way you thought it was? Correct springs, shock settings, sway bar settings? All the nuts and bolts tight? Is the alignment set correctly? Check your corner weights? Tire pressures?

HAVE SOMEONE ELSE WHO KNOWS THE CAR CHECK!!!It's amazing how much time we waste "engineering" when it was a simple error in the first place.

If it's not any of that, talk to someone who has the same car and make sure you're setup is in the ball park. Once you've ruled all that stuff out, then tell us what kind of car it is, what your settings are, and we might be able to fine tune it with you.

[RR]

Oh believe me I did all the basics, tire temps etc etc. Its a ITS bmw, with adj shocks, there are all set on soft settings, also did not toe in rear. Since its loose in tight corners wondered if I stiffened the front or tried some rear toe in?? Theory, guesses anyone???

[whenry]

what you seem to be describing is power oversteer. Do you have an open diff? I think that this is a design or driver input problem more than set up. Try feeding the throttle to the car rather than stomping on the pedal as you exit the corner. This is usually an issue for BIG hp cars.

[Quickshoe]

In addition to the above advice: Rear toe-out will increase corner exit oversteer (or lessen corner exit understeer). Don't know how much a BMW needs...try reducing the rear toe by 1/8" total and see if the problem gets better. I would guess that you aren't going to want more than 1/8" total toe in.

[chuck baader]

A BMW, espically an e30, must have rear toe...about 1/8". anything less and the car is wicked loose. Don't change anything else before you try again!!! Chuck

[Jake]

I'm not BWM expert, but with MR2s toe out in the rear make the back really tail happy.

Loose can be several things.

If the tail slides out in a quick transition - stiffen the front shocks and keep the rears soft.

If you are sliding the tail out cornering at a steady speed you need to stiffen the front bar and/or soften (or remove) the rear bar. Changing spring rates can also help.

If you are talking about power oversteer, you need to be gentle. An LSD will also help. Also loosening or removing the rear bar, and tightening the front bar will help keep pressure on both rear wheels.

[Quickshoe]

Originally posted by chuck baader:
A BMW, espically an e30, must have rear toe...about 1/8". anything less and the car is wicked loose. Don't change anything else before you try again!!! Chuck

Toe IN or Toe OUT?

My guess is IN.

[zracer22]

I disconnected the rear sway bar on my E30 and instantly turned laps 2 seconds quicker at Mid Ohio!

RR, email me for a more detailed description of all i've done, but the first step is to take off the rear bar.
[email protected]

[This message has been edited by zracer22 (edited April 19, 2004).]