how light is too light?

[pureboiracer 0]

going to get the flywheel lightened in the m20b25. just wanted to get an idea of how light is right for track use and not so light that you loose all your power?

[*Glenn* 855]

Try these guys

http://www.uucmotorwerks.com/

Or email: [email protected]..... a real nice guy. Thats where I got my flywheel from

[westy 614]

I had mine lightened to 6.3 kilos.

Quite a good compromise I thought. The gearbox might rattle and It might be a little easier to stall.

You wont lose any power with a light fly.

[|ncary 0]

The only thing you lose is the ability to clutch kick a skid. do it. Light as possible.

[westy 614]

The only thing you lose is the ability to clutch kick a skid. do it.

Rubbish.

Edited April 5, 2009 by westy

[Guest Ari Gold]

Tony and I had ours done by the same dude I think?

Out west, I forget his name, but he was an old digger and knew his stuff. Took mine down to 12lbs or so.

[320guy 0]

Had mine machined to 6kg aswell. Havent bolted it up yet though.

[westy 614]

I forget his name too but the place is called Balancing Specialties.

He was really good so have a chat to him.

[Guest FrantiC]

I just traded my stock m20 flywheel to a guy at that works at the BMW dealer here with a track car, Said he can't use a lightened flywheel so offered me his lightened one for my stock one. Took it home and put it on the scales, reads a mere 4KG.

I'm kind of scared to use it?

[320guy 0]

Take pictures of where it was lightened?

[Guest Ari Gold]

I just traded my stock m20 flywheel to a guy at that works at the BMW dealer here with a track car, Said he can't use a lightened flywheel so offered me his lightened one for my stock one. Took it home and put it on the scales, reads a mere 4KG.

I'm kind of scared to use it?

M20 fly's aren't forged or a billet, I'd be careful.

Just found a couple of before and after pics of mine: went from 19.6lbs to 13.5lbs

Before:

After:

Pretty clear where the meat has been taken out. No drama after 5K kms or so.

All the M20 8lb or so flywheels I've seen are alloy:

http://www.kormanfastbmw.com/e30drive.htm

http://store.nexternal.com/shared/StoreFro...reland&All=

[westy 614]

Snap.

Side

Edited April 6, 2009 by westy

[Guest Ari Gold]

Holy sh*t we've been helpful this thread.

http://www.finda.co.nz/business/listing/1w...ng-specialties/

Think his name was Bob.

[Guest FrantiC]

Would anyone dare use a 4kg (~8.8lbs) m20 flywheel?

Im not sure if I would want to have it in my car as I am turboing it... I don't know if it's safe or not.

[westy 614]

Ahhhhhmmmm.

The guy (I'm sure his name is Bob) did say that he could have removed more quite safely but 4kgs is getting pretty light.

Even though the flys are good quality nodular iron you you might want a steel one if you're going to pull decent revs.

I've also heard that light flys aren't a great idea on turbos???

[*Glenn* 855]

I think its a bit too light as well. I only went Stage 1 with mine, its 11.6 US pounds in alloy

Edit: I think it might be prudent to ring and ask Bob... it might be OK. Just tell him what your intentions are...especially with the turbo.

Edited April 6, 2009 by *Glenn*

[Guest FrantiC]

Yeah I kind of got "sh*t on", He talked to me ages ago when my car was in at BMW, pretty sure he said it was down to about 10-11pounds which wasn't allowed in his track car. So I was like yeah sweet. Then I got it, looked at it and was like hmmm looks like it's had a shitload taken out of it lol. Scales read a mere 4kg.. I was like wtf... Now I am scared to use it. Especially with a heavy duty clutch and a turbo'd 2.7 stroker I don't want it shattering cos it's pretty thin and had a whole lot taken out of it...

Edited April 7, 2009 by FrantiC

[pureboiracer 0]

just thought i would conclude this post.

got my flywheel down to 6kg. also put a 4.1 diff in at the same time.

now i go down the st and if i give it stick in second it will almost instantly light up and hit the limiter.

now i just need a slippy.....

[Forrest 35]

Sick.

[bmpower 3]

...you forgot 'and shoot flames' oli

[pureboiracer 0]

i want a photo of that.

[bemagirl 0]

i want a photo of that.

me 2!!

[BM WORLD 1286]

just had my e28 m5 engine one done by the guy in newlynn , very good results . M30 std flywheel for M535i was 10KG cut it down to 7.4KG e28 M5 runs a 7.5kg .

the engine does feel more willing now .

yes and also more rattles from teh gearbox now at low idle when its cold.

had the flywheel lightend and balaanced with the clutch pressure plate . he said it was a conservative lightening .

talking to auto clutch guy he reckons the crowd on the shore that do custom crome molly lighten flywheels work pretty good .

less likly to wrap like metal clutch surface plate on the ali flywheels

[pureboiracer 0]

if you were going to go that far it would probably be easier to import one of the billeted ones from england that weigh around 3 or 4kg

[Guest FrantiC]

Wonder what a 4kg flywheel would be like...? I should have tried it in the bone stock m20 stroker, man that thing was mental N/A. I could keep up with a B18C turbo civic pretty well (not even 2 car lengths infront of me at 190km/h). And that thing was pushing around 220wkw

Can't wait to have it turbo'd.

Edited April 20, 2009 by FrantiC