86 325 trans - i flywheel - m50

[Jason89i]

just completed another swap. this time i ended up using the e30 325es transmission with the i flywheel. there is a lot of "hear-say" being repeated.....some things true, some things distorted. so hopefully this can clear some things up.

i had a spare "i" single mass flywheel and clutch kit (5k miles) sitting around. the back of the "i" flywheel hit the oil pan bolts on the m50 when mounted. i had the flywheel lightened. i shaved the back "lump" portion of the flywheel off. this allowed it to fit the m50 without any modification to the pan bolts.

the getrag 86-325es transmission (which was originally installed with a dual mass flywheel) bolts up to the m50 with the 4 main large star bolts. the lower inspection plate bolt holes do not line up, they are 1/4-1/2" off from the e34pan.

the 325es starter (large case with backing plate) fit on the m50 block after grinding off a portion of a mount casting on the m50 block.

transmission bracket was whacked and welded to accomodate the 10deg rotation. sorry no pics. shifter linkage was twisted 10deg.

ok, here is where it gets tricky.....
i found the clutch slave did not press the fork/t.o bearing far enough to disengage the clutch. after further investigation i realized the dual mass flywheel assembly was +/-3/16" thicker than the "i" flywheel assembly. (i.e. 3/16" greater from face of crank mounting to face of pressureplate diaphram.) hence, the position of the t.o bearing was +/- 3/16" too far away to fully compress the diaphram......clutch no workeee. i could only see three solutions:
1. put a 3/16" spacer between flywheel and crank (then bolts experience greater twist and have less threads to hold them in.)
2. get a longer rod for the slave cylinder (then the fork is not perpendicular to the t.o bearing or shaft)
3. make the t.o bearing 3/16" longer.....from face of forks to face of pressure plate diapham. and thats what i did. i welded on some spacers to the t.o bearing tabs (the ones that press against the fork) which in essence pushed the t.o bearing 3/16" closer to the pressure plate. i have heard that the 323i euro t.o bearing that is 3/16" longer.....but that is "hear-say."..... can anyone (with experience) confirm ???

now it works. flywheel is mounted correcly, clutch pack is mounted correctly, t.o bearing presses snugly on press plate, fork is perpendicular to shaft......i drive off happily into the sunset.

cheers, jason

[SchnellerVert]

Jason, OT but are those Arik (E9nine's) wheels and tires on your car? Or did you like his style and use the idea?

[Jason89i]

Jason, OT but are those Arik (E9nine's) wheels and tires on your car? Or did you like his style and use the idea?

wow, that is off topic. im not sure who arik is and i dont think ive ever seen his car. but, it does sound like he has good taste. cheers, jason

[SchnellerVert]

I was spacing out I was thinking the style you had were on his.



and yes it was OT

[Pettas]

Anyone else any thoughts/experiences on this. I am about to do the conversion using a 87 tranny, need to see if this is the situation for all.

[Jason89i]

Anyone else any thoughts/experiences on this. I am about to do the conversion using a 87 tranny, need to see if this is the situation for all.

i believe the problem occures when you switch from dual mass flywheel to single mass. just noticed someone else experienced the same thing (not on the m50 though.) http://bimmer.roadfly.com/bmw/forums/e30/7360071-1.html

cheers, jason

[Pettas]

any way to tell if this will or wont work besides putting tranny in car and then trying to use the clutch?

[Jason89i]

any way to tell if this will or wont work besides putting tranny in car and then trying to use the clutch?

measure the distance from the block to the pressure plate fingers. figure out stock vs. new. if they're the same.....no problem. if they are different.....then you will have a problem. cheers, jason

[DanThe]

Ive just encountered this problem, I have an M50 engine with an M20 single mass flywheel and clutch, and im using an E36 325 gearbox.
I only noticed as I fitted the slave into the box that there was no resistance, you usually have to press the pushrod back into the slave about 1/2" to 3/4".
I have welded about an extra inch onto the end of the pushrod and this feels fine underfoot but have yet to drive the car to see how well it works.
This means that the release fork will not be at 90 degrees to the shaft. The release bearing will still have full contact on the clutch face but will this cause any problems?

[Jand3rson]

the getrag 86-325es transmission (which was originally installed with a dual mass flywheel)

The 86 325eS (at least the very early ones, mine is an 01/86) came with a single mass flywheel.

[Jason89i]

The 86 325eS (at least the very early ones, mine is an 01/86) came with a single mass flywheel.

so.....are you suggesting the flywheel was a single mass???? let me assure you, it was a dual mass flywheel. cheers, jason

[DanThe]

OK, sorted my problem out.
The E36 box I got had an E30 slave in it,,,,
heres the difference \/ E30 on left, E36 on right

[Rev Engineer]

Dan - So you went with the e36 trans with the m20 flywheel? Can you (or anyone else) confirm this combo works without modification with the e36 clutch slave?

I went this route too, just to avoid using that heavy hunk of e36 flywheel. Has anyone run into issues with the smaller m20 clutch not handling the m50 or s50/s52 motors?

OK, sorted my problem out.
The E36 box I got had an E30 slave in it,,,,
heres the difference \/ E30 on left, E36 on right

[DanThe]

Thats the setup im using, havnt driven on road yet so couldnt tell you about that part, but I know of people using the same setup and no complaints so far

[Rev Engineer]

Excellent...one less thing to deal with!

One other thing - does the e30 325i flywheel use the same length bolts as the s50/m50 with it's dual mass flywheel?