E46Fanatics - View Single Post - E30/36 LSD into E46 Swap
View Single Post
Old 04-03-2012, 03:33 PM   #41
Registered User
Join Date: Dec 2010
Location: Bel Air, MD/ WVU
Posts: 1,011
My Ride: '04 MB ZHP
Originally Posted by wanganstyle View Post
I have a empty e46 non m case here, I had it clearanced to fit a 188mm LSD center. I can email you a photo if the clearancing required to fit if you really want to know. It's a decent amount. With a ring gear attached and no spacer to adjust the centerline, it still needed clearance of the case. This was a side project to building up a nice os giken aftermarket unit for e46non-m. Took some spares off the shelf and tried to play the retro fit game. I change diff bearings and set ring /pinion gaps for diff builds, so it doesn't scare me.

The e46 cast housing is designed to clearance open diffs for installation.

if you mess with the spacing bolt on top cap of the e36/30 LSD center capsule the spider gear will also need a spacer. This opens up another very expensive/time consuming can of worms. My suggestion? Don't go there.

Perhaps adapting the e30 bearings and races and spacing would be smarter.
The e30/36 stub axels use a different standard e46, the circlip position is different, geometry also. Will the dust shields all line up post if Frankenstein-diffed?

The e46m unit can be re geared with Oem m division ring and pinion to 3.23 and 3.15 ratio. LSD center can be clutch type or gin visco-lok. I just built one up for turbo use (3.15 e46m clutch LSD diff). This would allow non m cars to Pnp a LSD in matching ratio to a 6500 rpm engine with a m3 rear subframe swap.

The e46m rear diff can be configured with genuine BMW parts to have a 4 bolt front flange that will mate with non m 4 bolt driveshaft 4 bolt pattern, this would allow upgrade of e46m of diff without buying a zhp 6 bolt driveshaft

Also the late model 2005/6 325ci/cabrio 6 speed SMG cars have a 4 bolt driveshaft in 6 speed length, they run a ZF 6 speed gearbox with identical length and mounting position in the body to the e46m gearbox.
So I can take the ring and pinion from a 3.15 open diff and swap it to the M3 rear and it will reinstall it with perfect fit?
Hornung418 is offline   Reply With Quote