In Reply to: ??? re: Strut Tower Stress Bar and X-Brace posted by Michael Fox on July 31, 2000 at 10:56:42:
2) On the E36 an undercarriage X-Brace is recommended for use with a front Stress Bar -- is there any similar commercial or custom product to create the same effect/solution on the E30? [Here's an informed discussion on the topic from the E36 perspective: http://www.gis.nsw.gov.au/staff/rnott/bmw/BMWText/technical/StrutBracesAndCrossBraces.html -- see, also: www.racepad.com -- strut bar dynamics]
Thanks for your informed thoughts.
1) Without any proof, I'll say this. The E30 benefits more from a strut tower bar than the E36's which have a stiffer chassis. You can feel the added stiffness in the E30 vs the E36. Pretty much any bar out there will provide some benefit. I happen to like the Eibach one personally.
2) I don't know of anyone that has attached an X-brace to an E30 M3. I'd like to see pictures if they have.
A couple of problems I would imagine are the fact that the E36 already has the necessary holes in the body and the subframe, and on top of that they're already threaded. Installation is a snap.
On the E30, assuming that the x-brace physically fits, you'd have to drill the holes and then find a method of adding threads to them. For the subframe attachment point there are threaded inserts (nutserts) that could be used similar to the early 95 M3's but torque spec on those bolts is very low. For the rear attachment points to the body I doubt inserts would retain the x-brace w/o spinning if you torque the bolts to the recommended specs. I sure hope someone does this and writes it up.