[rbryantaz]

Hi everyone, I was looking at a way to install a 4th mounting point to the e90 M3 rear differential and here is what I came up with.

This is similar one that I have seen for the e30 for the extension.

I am not aware of anyone that has done it for the e90 so I made one.

Back view:

(The center bolt is too close to the frame and will have to change to a countersunk flat bolt like the ones holding the bushing extension housing, the bushing extension housing bolts do have some room so those could be button head instead)

Front view:


This puts the bushing about 16mm from the frame so an aluminum spacer is used between the bushing and the subframe.

It requires a 9/16 bolt hole to be dilled through the rear subframe on the passenger side (nearly symetric to where the mount is on the driver side). This uses an e30/e36 bushing so they are readily available in pretty much any hardness that people desire. It could also be made as a solid mount with no bushing but that seems like overkill for most.

What does everyone think?

-Rich