rear camber correction options?

[ahlem]

I have worn the rear tires to the cords on the inside edges. I have some negative camber and offset bushings and wide 18" tires. The e30 sites have camber/toe correction kits that must be welded on to a removed subframe. I have lowering springs and adjustable Konis. What are the options? Replace expensive Falkans with new tires and live with it? I put over 25K miles per year on the car and will hit 350K this week.

[Rustam]

I have worn the rear tires to the cords on the inside edges. I have some negative camber and offset bushings and wide 18" tires. The e30 sites have camber/toe correction kits that must be welded on to a removed subframe. I have lowering springs and adjustable Konis. What are the options? Replace expensive Falkans with new tires and live with it? I put over 25K miles per year on the car and will hit 350K this week.

in order of editing:
(1) you have offset bushings and undesirable camber a clear option is to replace bushings to centric ones... no?

(2) offset bushings are offset precisely for the reason of affecting the camber. if you have them and the camber is undesirable then they are not put on right. they must be turned to set the desired camber. this is the obvious and clear straight forward option.

(3) mind you that turning the offset bushing besides affecting camber also affects toe. So the trailing arm must have two offset bushings since there are two dimensions for manipulation. And the distance from the front wheel has to be retained - this also is affected, a third incidental factor. This is not an easy task and can very quickly swell your head and frustrate. The easiest option is to simply replace the bushings to regular centric type, it will provide at least an improvement...

[ahlem]

(1) No. The camber and toe would be way wrong on my lowered car.
(2) You can affect the camber some but what I was wondering is whether you have to do the eccentric bolt mod to get the camber back to zero. On e30's you can only get so far with the eccentric bushings to correct toe and camber on a lowered car and then have to modify the mounts. You correct toe with the outer ones and camber with the inner ones.
(3) You bring up a good point I hadn't thought of. I will try to figure out where the offset bushings are positioned to see if I can adjust them more than I thought from my 6 foot away viewing. I hope that helps. Thanks.

[Rustam]

(1) No. The camber and toe would be way wrong on my lowered car.
(2) You can affect the camber some but what I was wondering is whether you have to do the eccentric bolt mod to get the camber back to zero. On e30's you can only get so far with the eccentric bushings to correct toe and camber on a lowered car and then have to modify the mounts. You correct toe with the outer ones and camber with the inner ones.
(3) You bring up a good point I hadn't thought of. I will try to figure out where the offset bushings are positioned to see if I can adjust them more than I thought from my 6 foot away viewing. I hope that helps. Thanks.

Well, what is the camber at this point? Or better - what is the difference in camber sought? For rough reference - at one foot separation a quarter of an inch is about half a degree. This may be a helpful info to hold in mind during examination of bushing position.

[bubba966]

Doesn't the M5 & M-Sport rear subframe have camber adjustability? Always forget what it was that was different about the rear subframe on the M5's, but I think that was it. Could always just swap in a rear subframe from an M5 rather than weld in that kit from Dinan or other places.

[Blitzkrieg Bob]

K-mak elipical RTABs

[genphreak]

Yes.

There are 3 settings depending on what you use:

- Std camber and toe
- Lowered camber and toe a la 'M-tech'
- M5 camber and toe (using offset bushings)

A page of the Bently describes the figures your alignment expert needs to achieve.