<E36> M3 Suspension Upgrade

[Jay Sala <jsala@xxxxxxxx>]

Thanks for the feedback.  I'll answer what I can.  Hopefully we can tie-up
the lose ends in swapping an E36 M3 suspension in an E36 325/328.  Please
read on below.   
>
>I agree, 328is with M3 suspension handles wonderfully, but your post didn't
>make it clear whether you swapped the strut bearing plates.  This is a key
>item since it sets up the camber and caster angle of the front suspension.
>Yes, it is possible to reuse the 328 bearing plates but if you're gonna go
>for the correct M3 suspension alignment, make sure to buy the new M3 strut
>bearings.  You can even swap them L-R to get an additional degree of
>negative camber.   

You've got a great point that future upgraders should take note of.  As for
my car, if by strut bearing plates you're referring to what the factory
calls the spring plate (which goes at the top of the strut and holds the
spring in place), then I do have the M3 piece (I'm getting this from a BMW
technical diagram).  I didn't swap the left and right sides, though (I had
forgotten about that trick).  If the strut bearing plate is something
different from what I've described, then I don't have the M3 piece on my
car.  

>Also, did you buy new spring pads?  I found that the '96 328 pads were a bit
>bigger (the '96 M3 springs have smaller diameter than 328 sport springs.
>'95 M3 springs are even slightly smaller in diameter).

Yes, the spring pads in the 328 and the 95 M3 are different sizes.  I
didn't have new spring pads at the time of the installation (this was
unforseen) and so right now the cars doesn't have spring pads.  To ask an
innocent question, what function do the spring pads play and how critical
is it for me to put them in?  Can someone shed light on the matter?  

>Also, what do you mean you can re-use 328 sway bar linkages?  My 328 front
>sways were attached to lover control arms by a short linkage.  The M3 strut
>linkage is about 2x longer.  Did they change that for '98?

No, the 98 328 still has the short linkages that attach the anti-roll bar
to the control arm.  You can reuse them if you don't mind attaching the new
bar to the control arm as well.  But, if you want to follow M3-spec, you
have to buy longer linkages that will attach the front anti-roll bar to the
strut housing instead of the control arm.  This is the route that I took.
The longer M3 linkages cost about $35 each ($70/pair).  
>
>Is there any reason why you didn't swap out the rear sway bar?  

As far as anti-roll bar size, my installer (a motorsports shop in Mountain
View that is NOT Dinan) claimed that the M3 has the same anti-roll bars
front and back as my 328 (the diameter and weight are the same, the only
difference is the linkage in the front).  I didn't verify this myself.  By
the way, from past postings in the digest pointed out that the 325/328
sport package has *bigger* anti-roll bars than the M3.  So, Mark, your
stock bars are bigger than the M3 bars you put on.  

Do let me know your feedback.  I'd be glad to compile all responses and
post the summary to the digest to guide other people in the future on this
upgrade.  

Thanks.

Jay Sala
BMW CCA, Golden Gate Chapter
Cross-bred 328i  

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