Fkywheels explained

[blocke]

Can anyone enlighten me on M20 flywheels? Single mass and dual mass, etc. And the practice of lightening one. Supposed to make the engine rev faster(less rotating mass)?

How much can an m20 wheel be lightened, and what else needs to be modified to accomidate it?

Anyone with experience with opinions on if its worth it if youve already got the tranny of to say, replace a clutch?

[lennon]

there are single and dual mass, the dual mass is a lot heavier and clearly two pieces. you probably have a single mass in your 325i. its common to resurface the flywheel when replacing the clutch, so it would be a great time to lighten it. any machine shop should be able to do this. nothing else needs to be modified.

[5KWattson]

I had mine lightened resurfaced and balanced for $140. It shaved 8 PBS from stock if I remeber right and on my m50 it makes her r3v happy as all hell

[ak-]

there are single and dual mass, the dual mass is a lot heavier and clearly two pieces. you probably have a single mass in your 325i. its common to resurface the flywheel when replacing the clutch, so it would be a great time to lighten it. any machine shop should be able to do this. nothing else needs to be modified.

How would you go about telling the machine shope to lighted your flywheel?
Or would they already know what to do?

Sorry for my ignorance, I never studied this subject.
All I know is that lighter = rev faster.

[NC325iC]

http://www.r3vlimited.com/board/showthread.php?t=155081&highlight=lightening+flywheel

http://www.r3vlimited.com/board/showthread.php?t=46880&highlight=lightening+flywheel