From digest.v7.n327 Wed Sep 24 20:43:42 1997
From: NeilMaller_at_aol.com
Date: Wed, 24 Sep 1997 19:41:50 -0400 (EDT)
Subject: Re: <E36 M3> 96/97 Front Suspension Mods

On Wed, 13 Aug 1997 Lew Becker <subecker_at_ix.netcom.com> wrote to the BMW-Digest
<snip>

>4. I intended to have camber plates installed in the M3 at the time the
>suspension work was done, but was informed that none are necessary or
>available for the 96/97 M3's. Dinan advised that offset strut mounts
>were among the changes the factory made to the 96/97 M3 suspension; if
>they are reversed (i.e., the right mount installed on the left side and
>vice versa), they yield the same negative camber as Dinan's "street"
>camber plates (.5 degrees negative).

I read this post with interest, since I have been experiencing excessive wear at the outer edges of my front Yoko A032R track tires, despite correct inflation pressures. I have attributed this to insufficient negative camber (stock is actually negative 3/4 degree, see below) for track use. At the Mont Tremblant Driver School one of my fronts got corded at the outer edge, but still had a fair amount of usabletread on the rest of the tire.

The 96 or later M3 has the front upper strut mounts offset to the rear (increases caster) and to the outside (decreases negative camber). This is easily visible if you remove the plastic covers on top of the strut towers inside the engine compartment. Swapping the upper bearing plates left/right preserves the rearward offset but reverses the lateral offset to increase negative camber.

A couple of days ago I dismantled the front suspension and swapped these left/right front strut upper bearing plates as suggested to Lew by Dinan. I was however a little concerned at the very obvious amount of visible negative camber that resulted. On the street the car basically drives OK, but the steering feel is somewhat reduced.

Today I took my 96 M3 in to have the alignment (toe in) checked after my messing with the suspension, and asked the tech also to measure the camber. Results, with the car empty and one third of a tank of gas are as follows:

• - Driver's side: 2 1/2 degress negative
• - Passenger side: 2 7/8 degree negative This is probably at the high end of acceptable for the track, but waaaay too much for street use. (For reference the stock camber spec is minus 46 minutes plus/minus 30 minutes, essentially equivalent to minus 3/4 of a degree nominal.)

Looks as if the Dinan info given to Lew is not really correct. I'm going to run the car this way at Mid Ohio this weekend, but plan to restore the normal setup afterwards.

Please note that the foregoing applies only to the 96 and later M3; the 95 has different front strut offset.

Neil
96 M3, a little knock-kneed at present