rear camber/toe

#1

my car has too much rear camber (about 4.25 deg LR, a tick under 4 deg RR). i’m 98% sure it has kmac eccentric bushings (the red ones). toe was about 1/16" in the last time i checked it. drives pretty good but the rear tires wear excessively on the inside, and of course it’s technically illegal (go ahead and call me a cheater, i’m used to it).

question is, what can/should i do about it? futz around with the kmacs as much as i can and hope for the best? assume i have one (or two) bent control arms? drop the subframe and make sure everything is ok? weld on some sort of adjustable bracket or tab that i seem to recall reading about?

#2

Remove rear subframe.
Purchase and install Ireland RTAB weld-in kit along with standard BMW rubber bushings, maybe even the BMW offset bushing to get the camber number back to 2.0. Camber is the inner-most of the arms, so play around with the offset circle that you have with your k-mac bushings and see how much a rotatation gets you.(I think about 2.0.) Make note of the orientation as you work to get the camber out,You may want to put the BMW offset in at that position.

Reinstall, align and mark alignment with color paint for reference if it comes loose (and it will come loose) or tack weld the fasteners. That is what I did last off season on the 911 and 241.

You are correct about the rules, but I can’t see why anyone would protest a car that was goobered-up so bad as yours is. But, them is the rules, and the paddock size gets bigger with each new race, so get it fixed to avoid potential conflict.

RP

#3

thanks RP. unless i’m mistaken grace was DQ’d at nationals for excess rear camber, and i’m planning on mid ohio in 2011 so gotta be fixed.

#4

My pleasure to help.
If I can’t run with all of the young guns there is solace in helping youse guys out.

RP

#5

i assume you’re suggesting both of these:

http://store.nexternal.com/shared/StoreFront/product_detail.asp?RowID=210&CS=ireland&All=

http://store.nexternal.com/shared/StoreFront/product_detail.asp?RowID=209&CS=ireland&All=

are these essentially the same thing, or are the ireland pieces better? only ask because i won a $50 vac gift certificate at the last bmwcca race.

http://store.vacmotorsports.com/vac---semi-trailing-arm-rear-camber-toe-adjustment-kits-p2019.aspx

#6

VAC description is 100% correct. Did not see a picture on their site.?

Links to Ireland didn’t work.Go for it.

RP

#7

JT, with your rear camber/toe fixed you should see a decent improvement in straight-line speed.