Originally Posted by Sick Speed
The diffs change from M3 to M5 - 3.91 in M5 and this is what I am guessing will be in the new M3. I was just looking for some confirmation. The 3.91 is what I installed in my 04 M3 and the difference from the standard diff is night and day. 4th gear feels like mid peak 3rd and it lists the rear to the right when I get on the throttle.
In the BMW Press Release specifications the final drive ratio is listed as 3.846
. It may be different when the 7-speed DCT comes out.