3.15 3.64 3.38 lsd my review ( Performance Gearing)
Some of you may have read my review of a used 3.64 LSD I bought used from a member. I liked it a ton at the time, but first was short and I didn't love running 3,000 rpm at 75 mph on the thruway. It was a dramatic improvment over stock though.
That read end broke- a tooth in the gear set broke and scattered through the diff so I put the stock one back in and called the guy who built the 3.64 lsd, Jim from Performance Gearing.
He proposed what sounded like a wonderful solution- a 335i diff which is larger and rated for twice the torque of the standard 330i 3.15 one legger.
I opted for the 3.38 this time which seemed to be the Goldie Locks setting, just right. It sure is- the car just screams through the first 3 gears, and is civil on the highway.
** complications involved** The 335i diff is larger, requiring a shorter drive shaft. Jim sent me a e36 m3 drive shaft which was the right length, but the splines and the carrier bearing didn't work. He then sent what I think was a 323i e90 driveshaft- right length overall but still didn't work so my mechanic used the front 330i ds section with the 323i back half (I think) and made it work. Plenty of spline and no vibes.
The car feels new. I love it and can't wait for autocross and the next de at watkins glen.
If you are thinking of getting a diff from Performance Gearing- go for it, Jim is an stand up human being and enthusiast and only wants what is best for his customers, a true asset to our community.