What flywheel/clutch combo for m20 and m50

[Cm50]

Please help me out, all of the clutch variations have me so confused..
I have an '88 325is that needs a flywheel. It came with a twin-mass anchor that was worn out so I bought a single mass flywheel on ebay, supposedly from an '87 325i. However, the pressure plate locating dowels are not the same. My '88 twin mass has large dowels spaced evenly between the threaded holes whereas the single mass has skinny dowels placed much closer to one side and a litte farther from the center so they obviously use different pressure plates even though the diameters were the same and I think the ring gear placement (the starter does engage). Btw I have a brand new Sachs pressure plate and clutch disc (solid) that I bought for a '93 525i (m50 donor). However, the m50 is going to the shop for a rebuild (m3 cams and maybe 2.8 stroker) and I'd like a clutch in the meantime without wasting money.

Ok, so my question is, what can I do to have a flywheel and clutch for cheap for the M20 until I'm ready for the swap and then possibly use the same setup on the m50 (will most likely be using Getrag S5D 250G from e34). A few options, pleaes tell me which if any of these will work:

• Pull M50 twin mass from e34 and use in M20 - free, but I want something lighter weight - is this compatible without modification?
• Buy pressure plate for the single mass (small dowels) or have a shop install the large dowels and have it lightened while I'm at it - will this work in the M50? what model pressure plate do I look for if using the small dowels?
• Buy new aluminum lightweight flywheel - what model to buy for that will fit both engines without modifications? I'm worried that the starters may be different..

It appears from pictures at bavauto that the pressure paltes for the thin, offset dowels is for M3 flywheels??

Thanks,
Colin

[mentaleeill]

just buy m20 single mass clutch setup.

[Cm50]

Will the M3 clutch kit work on the 325i single mass flywheel?

[Jason89i]

Will the M3 clutch kit work on the 325i single mass flywheel?

no.

pressure plates are specific to flywheel. ie...e36-325 pp only fits the e36-325 flywheel. the e36m3 pp only fits the e36m3.

cheers, jason

[trent]

no.

pressure plates are specific to flywheel. ie...e36-325 pp only fits the e36-325 flywheel. the e36m3 pp only fits the e36m3.

cheers, jason

This is wrong depending on which M3 we are talking about. I used an E30 M3 Clutch kit on my 8lb JB Racing Flywheel for an M20 bolted to my M52.

[Cm50]

jason, what exactly is different? From what I can tell they are just about all 228mm discs, and from pictures it appears the locating dowels are the same. Do the M3 pressure plates have more surface area, or is it just an M3 pressure plate because the load springs are stiffer?

[Jason89i]

This is wrong depending on which M3 we are talking about. I used an E30 M3 Clutch kit on my 8lb JB Racing Flywheel for an M20 bolted to my M52.

i was speaking of the e36.....but good catch.

jason, what exactly is different? ..... and from pictures it appears the locating dowels are the same. Do the M3 pressure plates have more surface area, or is it just an M3 pressure plate because the load springs are stiffer?

for the e36's......the dowel pins are different. not sure on the diaphram. you might want to ask dave (1990m3). he has discovered that early and late e36m3's have different pressure plates, diaphrams are sprung differently....something like that.

cheers, jason

[FredK]

Yes, S50 M3s and S52 M3s have different dowel pins on the PP, as well as a slightly different outer diameter (clutch disc is the same diameter, and even same PN on the ETK, though).

I just learned the hard way after buying a lightweight M3 flywheel, and finding that my early M3 pressure plate does not bolt up. CRAP! I'm just going with the boat anchor S50 stock flywheel for now.