The car has no turn in...Caster problem?

[Villanuevas_BMW]

This is one problem I have been dealing with for a long time. It seems that the the car has no turn in and is a bit slow to respond. The battery is in the back, the ac compressor has been tossed, the hood is now carbon fiber, the fenders are fiberglass, at LEAST 100 lbs have been dismissed. Front tires are a bit wider, and runnning neg 2 camber in front with IE adj camber plates. Still not happy. However I started to notice a view things. As a 2002 gets lower to the ground, the front tires gets pushed back into the wheel well toward the cabin. Also noticed on my M3 when the wheel is turned, more negative camber appears, much like a bicycle. Which leads me to believe the problem is caster. It seems that the top of the struts need to be pushed inward and backward, has anybody done this?(besides the 2002 with M3 suspension) The radius rod has been shortened by pushing the thread inward on the rod to stop pushing the wheel backward. Besides this I have no idea how to adjust caster and Im not ready to chop the chassis just yet.

[NickVyse]

I think I might have the same problem. Similar set-up to you. Here's one persons solution, but not sure who it is or where they got their kit from.

[steve k.]

What speeds are you talking about? Low or high speed turns? What is your toe set up and what is the camber/toe inthe rear? How does the car feel coming out of the turns?

steve k.

[c.d.iesel]

too little caster ?

move the top of the strut BACK

or

move the bottom of the strut FORWORD

I like the K-MAC upper strut mounts for their

urethane filling- which back to back comparision to

new stock rubber mounts 'sharpens' up the steering

feel and reaction off of center ahead. No added noise or

vibrations. Some of the 'RACE ONLY' upper mounts

lack compliant mount material and are just metal to metal bearing mounts. These require constant inspection, cleaning, and lubricating

for safe extended 'road' use. The K-MAC mounts can adjust Camber

and Caster - being limited only by the coil spring making contact

inside the inner wheel well. Sufficient range for sport driving and track use adjustments. For all out maximum neg. Camber and pos. Caster

angles - Coil Over modified struts are needed. (or use of old First 5

series lower control arms?).

Re check your TOE with every change to Caster & Camber !

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[TobyB]

Caster will affect self- centering, and to some degree improved cornering at significant loads and steering angles.

And these cars have pretty consistent caster as you increase camber by bringing the top of the strut in. The lower locating links are almost in the same plane, so there's less interaction than you might think, or than you'd get in a Honda.

Initial turn- in is greatly affected by toe, though- the difference between 1/4" in and 0" in is night and day. And no toe with some real camber (3deg) will go EVERYWHERE but straight on the less- than- average roads we have around here...

I run 0 on the track, but then toe in about 1/4 turn each side if I'm not tracking much. It's a lot more comfortable...

hth,

t

[Villanuevas_BMW]

What speeds are you talking about? Low or high speed turns? What is your toe set up and what is the camber/toe inthe rear? How does the car feel coming out of the turns?

steve k.

Thanks guys, this is exactly why I joined this forum! Great info. The problem is at higher speeds. I know inertia plays a good part but I know it shouldnt be this bad. The car tracks well out of a turn. I also forgot to mention that my tire setup is pretty dumb too. 15/215/50 in front, and 15/225/50 in the back without the power to back them.

[steve k.]

How adjustable is your suspension?

you can soften the front bar/stiffen rear bar or lower front tire pressure.

Also lowered 2002 will generate a lot of negative camber in the rear. you can get to almost -3.5 degrees. That is bad. If you cannot adgust that you will have to compensate. the ideal situation is -3.5 front, -2.5 rear camber. You can increas the toe out as compensation to see if that will correct the issue.

steve