E46 M3 rear axle on Z4?

[Andrei]

Hello everyone,

I have recently bought an 3.0si roadster. It is an excellent car (my first Z) and after doing all the usual service work and maintenance I am looking for something more so I decided to try to get an LSD on it and maybe some bigger brakes so I am looking at swapping the complete rear axle with an M3 one.

After a bit of research on bmwfans.info I have found out that the rear carrier is common between Z4M and E46 M3 and I assume it will fit Z4 non-M as well.

What I don't know yet:
Prop shaft flange - will the 3.0si flange fit the M3 diff? Any idea on where to get diameter dimensions from?
ABS sensors - the part number is different on the M3. Are they interchangeable? :roll:

Thanks for any input and I will keep you updated.

 

[srhutch]

stevie.w has done it

http://www.z4-forum.com/forum/viewtopic.php?f=11&t=55073#p805014

 

[Scooba_Steve]

If you just want an LSD then why not go for an M Factory one?

 

[markplant]

If you just want an LSD then why not go for an M Factory one?

+1
Iirc machine monkey has this one an is more than happy
Also if you went with the m3 axle I'm fairly certain you'll need m wheels due to off sets

 

[srhutch]

If you just want an LSD then why not go for an M Factory one?

+1
Iirc machine monkey has this one an is more than happy
Also if you went with the m3 axle I'm fairly certain you'll need m wheels due to off sets

Yep, axle is shorter so will need more meat on the wheels.

 

[PerryGunn]

If you just want an LSD then why not go for an M Factory one?

+1
Iirc machine monkey has this one an is more than happy

Yep, and I have the Quaife LSD - so there are a couple of options that are a lot less work than the M3 axle swap....

 

[Scooba_Steve]

Sorry should have added - if you want bigger brakes then I don't think just doing the back is safe or worth it.
Plus, the stock brakes are pretty good.

 

[Andrei]

M Factory - it seems to cost around 1200$, the money for which you can get a complete M3 rear axle. M3 rear axle has some very nice to have things: higher final drive ratio, stiffer sway bar, bigger brakes - and YES the front brakes are a must if you do the rear ones. And if the propeller shaft flange is the same as on my car it looks to be bolt on, to me it seems to be roughly the same amount of work as if I were to do the poly bush conversion.

However I need to fully understand all the details behind the M3 conversion before buying the parts...

 

[pokeybritches]

There was a guy on another forum that advocated hard for the M3 rear end swap. The rear cover needs to be trimmed and Z4M driveshaft must be used. Overall he thinks it's easier than swapping pumpkins.

I personally have swapped the pumpkin twice on my M54 Z4... first to a 3.64 open diff, and then to a 3.46 Quaife. I like the Quaife better than either of my M's trick diffs. I could see the 3.64 being useful on an N52 car, but it's a little aggressive for a daily-driven M54 engine (at least if it's supercharged).