Author Topic: M20 fly wheel (Read 5531 times)

oldtimer · « **on:** April 30, 2007, 08:52:22 PM »

One of the few things that was suggested to add power to this particular model is to do a M20 fly wheel conversion. Has many E42 owners done this mod? if so, is there a kit to buy that includes all the necessary parts. What does the mod entails? I would like to do it to mine when I get around to replacing the clutch which has not arrive yet.

Ben

D. Clay · « **Reply #1 on:** April 30, 2007, 10:54:03 PM »

Cheapest is to get a flywheel, clutch, and pressure plate from an M20 core motor at a local salvage yard or from someone that bought a motor to replace a blown one. There's a spec for the clutch disc thickness that is a pretty good indicator of what's left of it. You would need to get that special throw out bearing from some other model and starter pinion.
If you turn down the M20 flywheel on a lathe it will clear the M42 block and you won't need the spacer.
All of this is detailed in other threads here if you search.

b318isp · « **Reply #2 on:** May 02, 2007, 11:34:56 AM »

It will not give extra power but it will reduce the inertia of the engine allowing it to accelerate a bit faster in the lower gears.

A simpler job is to use a single mass flywheel from an M40 318i/316i from Europe as it is a straight swap, however it is heavier than the M20 conversion.

D. Clay · « **Reply #3 on:** May 02, 2007, 07:56:22 PM »

What would it cost to ship a flywheel & package across the Atlantic?

b318isp · « **Reply #4 on:** May 03, 2007, 05:22:31 AM »

Yuu'd just need the flywheel as the rest of the clutch assembly is common. I'd imagine it would be dear enough - perhaps $100???

AL GReeNeRy · « **Reply #5 on:** May 04, 2007, 12:48:42 AM »

Quote from: D. Clay;24900

Cheapest is to get a flywheel, clutch, and pressure plate from an M20 core motor at a local salvage yard or from someone that bought a motor to replace a blown one. There's a spec for the clutch disc thickness that is a pretty good indicator of what's left of it. You would need to get that special throw out bearing from some other model and starter pinion.
If you turn down the M20 flywheel on a lathe it will clear the M42 block and you won't need the spacer.
All of this is detailed in other threads here if you search.

when you say turn down the flywheel im guessing you mean the side facing the block? would the 8lb. jb lightweight flywheel work without cuttin anything? its cheaper and lighter than the m42 lightweight flywheel so im planning on doin the m20 conversion.

as for more power, b318 is right. it wont give you more power but it will allow the engine to rev more freeely.. and having just a stock m20 clutch would allow you to modify your m42 without worry of burnin the stock clutch (if you could ever get enough power to do so).

oh yea and saving 10-20lbs off the front of your car is ALWAYS a PLUS!!!

anisotropy · « **Reply #6 on:** May 11, 2007, 04:38:21 AM »

Have you done this b318isp? My clutch is on the way out but there's no way I could afford 2-300 hundred quid extra for an aluminium one and it seems a waste not to change the flywheel.
BTW try german ebay for a euro flywheel I don't know about the US but to uk their postage is always dirt.
Kevin

b318isp · « **Reply #7 on:** May 11, 2007, 07:35:06 AM »

Quote from: anisotropy;25444

Have you done this b318isp? My clutch is on the way out but there's no way I could afford 2-300 hundred quid extra for an aluminium one and it seems a waste not to change the flywheel.
BTW try german ebay for a euro flywheel I don't know about the US but to uk their postage is always dirt.
Kevin

Yep, I have a single mass flywheel. I got one on ebay.de for �32 including deliver to Ireland.

anisotropy · « **Reply #8 on:** May 11, 2007, 08:43:20 AM »

Quote from: b318isp;25452

Yep, I have a single mass flywheel. I got one on ebay.de for �32 including deliver to Ireland.

Searching for 'Schwungrad' now, seems a really good compromise, thanks for the tip.

odbod · « **Reply #9 on:** May 11, 2007, 09:30:35 AM »

There is another thread on this here with more information...
http://www.m42club.com/forums/showthread.php?t=2063