Author Topic: aluminum flywheel (Read 4854 times)

gravyface · « **on:** November 23, 2009, 09:22:34 PM »

Anyone replace their stock flywheel with an m42 aluminum flywheel on their 318is? Looking for parts sources, opinions before and after, etc.

Bmex318i · « **Reply #1 on:** November 23, 2009, 10:46:54 PM »

Im running a 12lbs from an e36 m42.... from HPF. Works fine the only bad thing it drops speed while shifting, but works good..

Andy_Casey · « **Reply #2 on:** November 24, 2009, 03:47:56 AM »

Road or track use? For road use you're better off with a lightened SM wheel IMO. Are you runnign SM or DM FW at the mo? Fitting a SM wheel to my S2 made a really nice difference, a mate has been running a lightened SM on his IS for a while and it's really nice.

gtatbrissy · « **Reply #3 on:** November 24, 2009, 04:47:44 AM »

http://www.m42club.com/forums/showthread.php?t=9629

Andy_Casey · « **Reply #4 on:** November 24, 2009, 07:04:39 AM »

LOL @ 'that's dangerous' post. Seen many flywheels like that, thing to do is get it done professionally and then balanced along with the clutch assembly, better for revs, better for smoothness.

gravyface · « **Reply #5 on:** November 24, 2009, 08:44:41 AM »

Quote from: Andy_Casey;82004

Road or track use? For road use you're better off with a lightened SM wheel IMO. Are you runnign SM or DM FW at the mo? Fitting a SM wheel to my S2 made a really nice difference, a mate has been running a lightened SM on his IS for a while and it's really nice.

Street/autox, and car's my daily. I'm thinking the m20 flywheel conversion sounds like a happy medium.

bmwman91 · « **Reply #6 on:** November 24, 2009, 11:39:02 AM »

I recommend the M20 flywheel conversion (it has to be from the post 1988 "i" motor).

http://bmw.e30tuner.com/my318is_pic_rebuild6.php

As I discovered, you actually only save 5lbs total because the M20 pressure plate is heavier. Still, that's a 12% reduction in mass (and the M20 flywheel has less of it concentrated around the outside diameter, which also helps). From what I understand, you can have the M20 flywheel machined down to ~11lbs from its original 19lbs. It is just hard to find a reputable shop that is willing to do it!

1991 E30 M42 · « **Reply #7 on:** November 24, 2009, 02:18:45 PM »

I have a 9lb m20 flywheel from metric mechanic. They also machine it to accept the m42 starter ring so you do not have to change the bendix on the starter

fiftytakedowns · « **Reply #8 on:** November 24, 2009, 02:33:20 PM »

Quote from: Bmex318i;82003

Im running a 12lbs from an e36 m42.... from HPF. Works fine the only bad thing it drops speed while shifting, but works good..

Im wondering if the aluminum flyhweels have the little pin thing for TDC if you want to do a timing chain job.

gtatbrissy · « **Reply #9 on:** November 25, 2009, 03:29:52 AM »

Quote from: fiftytakedowns;82028

Im wondering if the aluminum flyhweels have the little pin thing for TDC if you want to do a timing chain job.

nah i would be on the crank, mine didnt have any marks for tdc

Andy_Casey · « **Reply #10 on:** November 25, 2009, 05:51:24 AM »

I would expect to get a FW lightened over here at a decent machine shop for �100. MM are offering it for $350 but 11lbs is quite light!

http://www.metricmechanic.com/prices/pricing-clutches-and-flywheels.php

Why not source a SM flywheel from this side of the pond, got to be a few about here and certainyl in germany on ebay.de... there are 5 secondhand ones on there for between 30 and 40 euros from the same place. Maybe he'll send the lot out to the states, never can tell on ebay.de.

http://shop.ebay.de/i.html?_nkw=m42+schwungscheibe&_sacat=0&_trksid=p3286.m270.l1313&_odkw=e30+schwungscheibe&_osacat=0