Author Topic: M42 Aluminum Flywheel options (Read 12913 times)

fiftytakedowns · « **on:** October 02, 2009, 10:27:49 PM »

I got a brand new clutch kit for my 318is as a gift, and although I was planning on going the m20 route, It would be damn rude to not use it, especially, if the guy that got it for me is my boss, and owns the shop.

Ive seen some flywheels out there that are like 600 bucks. WOW I dont know if I can justify throwing that into the car, when I feel like I want to do a swap in the next couple of years. Any cheaper lighter flywheels (anyone have any for sale?)

Does the flywheel make a big difference, or should I jsut replace the clutch anyway without swapping the flyhweel.

(plan on camming the motor, and possibly ITBS if I deciden not to go 24 V)

roundel318 · « **Reply #1 on:** October 03, 2009, 12:22:10 AM »

I have seen some lightened BMW flywheels that result in smoother behaviour and with the AC on, etc as opposed to a spendy aluminum one (perhaps the teeth wouldn't be as likely to break either?) I imagine it requires some other random bits but I have been told it is one of the best ways to go if you aren't on the track (no AC, yada yada)

iamcreepingdeath · « **Reply #2 on:** October 03, 2009, 12:29:58 AM »

I have heard amazing things about lighter flywheels, like its a completely different car, etc. And i can imagine losing all that rotational mass would really pep up the engine.

fiftytakedowns · « **Reply #3 on:** October 03, 2009, 01:21:18 AM »

Quote from: roundel318;79340

I have seen some lightened BMW flywheels that result in smoother behaviour and with the AC on, etc as opposed to a spendy aluminum one (perhaps the teeth wouldn't be as likely to break either?) I imagine it requires some other random bits but I have been told it is one of the best ways to go if you aren't on the track (no AC, yada yada)

It is a dual mass flywheel, not sure if they can really lighten it..

1mochi · « **Reply #4 on:** October 03, 2009, 10:36:26 PM »

I have a JB Racing aluminum flywheel in my M20. I just had my engine rebuilt with S50 M3rods so have lightend the rotational mass on my engine. Just keep in mind you will hear rattling from your main transmission shaft with the aluminum flywheel; it's more pronounced with the S50 rods. I only hear it when the car is in neutral at idle with the clutch engaged. Lower mass makes it spool up a little quicker, but having less mass means starting on a hill a bit more challenging. I commute in San Francisco and my flywheel friction surface was in excellent shape with over 60K miles on it; I had it replaced by JB even though they said it did not require it. I have no regrets on having an aluminum flywheel. If you decide to buy one, I recommend JB Racing; they have the facility to rebuild it later. Also, they have excellent customer service. If the prices seems too good to be true, I would question the quality of the flywheel; you do not want this piece of equipment failing when you are winding up your engine. Consider JB Racing if you want a quality made flywheel.

roundel318 · « **Reply #5 on:** October 04, 2009, 12:52:55 PM »

Quote from: fiftytakedowns;79345

It is a dual mass flywheel, not sure if they can really lighten it..

I think they take a single mass and retro it to fit the M42.

1991318is · « **Reply #6 on:** October 04, 2009, 05:50:20 PM »

Quote from: roundel318;79398

I think they take a single mass and retro it to fit the M42.

They can, its from an m20, but the OP already said he doesn't want to go M20 route. I'd still suggest it though, n terms of prices, can't beat m20 since its a huge difference in weight from factory m42 w/o the price of an expensive aluminum one.

fiftytakedowns · « **Reply #7 on:** October 05, 2009, 01:47:34 AM »

I wish someone in the greater bay area has one I could test drive.

visionracingdevelopments · « **Reply #8 on:** October 06, 2009, 06:09:28 AM »

Lots of people think they have dual mass wheels when they don't. People were going on about it so much I was convinced I had one until I saw it.

The single mass M42 wheels are easy enough to lighten. I've taken mine down to just under 7 kilos from a woping 12.5kilos! I haven't yet driven the car so cannot comment on how it feels.

fiftytakedowns · « **Reply #9 on:** October 06, 2009, 08:27:56 PM »

my car had AC so I assume it has teh dual mass which was designed for the dual mass.

Boosted E30 · « **Reply #10 on:** October 07, 2009, 07:57:55 PM »

I have an aluminum flywheel from bmp design its 11lbs i think and made a huge difference the engine revs way quicker and is much more alive then before. if you got the cash i would definatly say go with an aluminum one.

iamcreepingdeath · « **Reply #11 on:** October 07, 2009, 08:03:17 PM »

for the ultimate upgrade, do the swap to the M20 flywheel, but use an aluminum lightweight M20 flywheel. They weigh like 8 pounds.

fiftytakedowns · « **Reply #12 on:** October 08, 2009, 10:46:35 PM »

Anyone know where to find these flywheels for under 600 dollars, everywhere I look they are BANK.

iamcreepingdeath · « **Reply #13 on:** October 08, 2009, 10:53:37 PM »

yeah that sounds about right, you won't get anything decent for much less than that.

fiftytakedowns · « **Reply #14 on:** October 09, 2009, 12:00:57 AM »

Worth the 600? with a new 318 clutch

or just do the m20 flywheel conversion, and not tell my boss I didnt use his clutch.

Edit

$420?
http://www.horsepowerfreaks.com/performanceparts/BMW/318/Flywheels/Flywheels
seems to be for the m42b18 from early e36s

found another one for 360$ on a diffrerent website same brand