M52B28 - ZF Trans - M20 SMF questions

[dsmcooper]

I just finished my swap of an M52 from a 1996 328i. When I first drove the car the clutch engage point was extremely low. I had to put it all the way to the floor to get it to disengage. After driving it three times now the clutch pedal is stuck at the very top and is hard to press, so hard that I bent the pedal when trying to push it with my foot. Now I can shift into all gears while idle so it's broke and I'm going to pull the trans to find out what happened. Right before this happened I had a grinding feeling in the pedal when I pushed it all the way to the floor. Perhaps the TOB went through the PP fins? Or maybe the clutch fork got somehow dislodged?

Here is what I used:

1991 E30 325i Originally Automatic
M52B28 from 1996 E36 328i
ZF transmission from the same 1996 E36 328i
M20 single mass flywheel from 325i - machined 5mm off the back to clear the e34 oil pan
*I think* I used M20 flywheel bolts (shorter) but it's been a while since I installed them so I can't be sure
M20 stock clutch and pressure plate kit from M20B25 325i E30
M20 Throw out bearing (TOB) from the same clutch kit
E36 slave cylinder
M20 starter from the E30
E36 Clutch Fork

I have done a ton of searching and I can't find the answer for my exact setup so I'm hoping someone has some experience and can help me out.

Do I need to use the 323i TOB from an e21?

Do I need to use the e30 clutch fork with this trans and flywheel setup?

At this point, I want to do this right. What would be the ideal clutch to use? Should I consider upgrading to something stronger which will still enable me to use the light 325i single mass flywheel from the M20B25?

Here is what I'm thinking, please let me know if this is going to work?

M52b28
ZF trans
M20 SMF
M20 starter
e21 323i TOB
M20 clutch and PP
E36 clutch fork
E36 pilot bearing
E36 Slave

[mtech325]

Based on your proposed setup, your clutch flywheel combo should work (mine is nearly the same aside from the TOB).

To answer your questions:

1. No, you do not need the 323i TOB from an e21, the standard m20 325i TOB will also work (and is a part shared with the non-M3 e36).

2. The e30 and e36 clutch fork should be interchangeable (part numbers seem to have been updated/superceded over the years), but to be safe I can confirm the e36 clutch fork works with the m20 325i SMF.


Otherwise you can install a complete e36 328 or M3 flywheel & clutch kit combo (along with the e36 starter), as it was designed to be used in the ZF320. There are also SMF flywheel options for the e36 clutch in case you don't want to use a factory DMF.