curing understeer

[dave5]

who can help me with some idea's as how to cure understeer?

my car is back wheel drive, fully stock (328i).

i'm interested in a couple situations. first would be in slow corners like a solo2 hair pin. second would be high speed sweepers, like turn 1 or 3 a mosport.

at mosport i usually use throttle lift to get the back moving around. i've heard guys talk about different tire pressures - not sure what to do there. any other ideas would be great too!

dave

[Marsh]

What kind of toe do you run?

[ice/solo racer]

Generally speaking increasing tire pressure will increase traction,so increasing the front pressure will help with the inherent understeer.This assumes that the front pressure isn't allready optimized.
You can test by increasing front pressure a couple pounds at a time untill the understeer returns/worsens,at that point if the understeer is still too much for your liking than you can start reducing rear pressure in the same fashion.
The preasure needed for solo 2 and high speed sweepers will most likely be different,so if the testing is done in a solo 2 event use caution in the sweepers untill the correct pressure for the higher speed is determined.(I hate seeing where I just was!)
You could also as Marsh suggested use different alignment settings,0 toe up front should help and not increase tire wear much.Adding negative camber up front would be a big help,or reducing the rear negative camber your bimmer comes with,not sure if adding parts like camber plates or front sway bar is in your plans.The front sway bar would help to things at once,help limit body roll and subsequent camber gain(does however increase the load on the outside front)and if you car doesn't have a limited slip diff than the front bar will transfer weight onto the inside rear and help reduce inside wheel spin on corner exits.
Stiffer/lower springs will also go a long way to making the car more responsive but again not sure if that was part of your plan.
Hope this helps you out.

[msix]

What tires are you using, are they 'All Season' or are you using a good Performance tire?

It does not sound to me like you got your Mosport 'Experience' through a Performance Driving School.
There you would have learned some BASIC skills, like the dynamics of the car and what impact Tire pressure has on the handling of the car, etc.

First step, a good Performance tire and a Performance Driving School with a well known Car Club.

As for SOLO II, Hairpin, all I would recommend is:
SLOW IN, FAST OUT!!!

Next step, some Suspension upgrade (Bilstein, etc.) and later other refinements of that.

If you have done already the first step, go right to the next step, helps guaranteed. :D