Flywheel?

Va914 · 02-01-2002, 03:53 AM

I have the flywheel off my 2.0L and have a question. Should I have it turned before installing a new clutch? What is an average price for this?

Thanks

Jim Smolka · 02-01-2002, 04:02 AM

Yes, have your flywheel turned. They can also check to make sure it is within spec.

The cost should be in the $30-$40 range depending on where you live...

prattrc · prattrc's Garage

Kerry,

There's a place off of Staples Mill that quoted me $45. If you hear of a better place in Richmond, let me know.

Va914 · 02-01-2002, 05:25 AM

Thanks..
I'll check around. Can a bigblock machine shop handle the 914 flywheel okay? I know not to take the aircooled blocks to a bigblock shop, but what about the flywheel? Do you think i'll be okay?

Thanks

Joe Ricard · Joe Ricard's Garage

The big block guys might look at you funny because our flywheels look different. But as long as the have a lathe they should be able to do it. It might help to bring them the specs that you want checked. They may not have the reference handy.

Just did mine two months ago. works great with a 911 friction disk and pressure palte form PP

Nice light pedal pressure and smooth take up. In retro spec it is alot nicer than my 1700lb kenedy I had on my hot rod VW. Athough there is something to be said for side stepping the clutch at 5 grand.

SteveStromberg · 02-01-2002, 08:00 AM

Be sure they cut the area that the Pressure plate bolts to the same amount as they cut from the face of the flywheel, Steve

oredith · 02-01-2002, 08:41 AM

man, you guys are getting RIPPED OFF!..

i drive down the street to Rimco, plop down my flywheel, get it balanced, surfaced, and lightened for 60 bucks.. i think the surfacing was $25..

Va914 · 02-01-2002, 09:00 AM

How much can you lighten the flywheel with out the engine dropping RPM's too fast?

Thanks

oredith · 02-01-2002, 09:37 AM

i believe mine was lightened to 13lbs (though i'd have to look on the little paper to be sure).. but i've heard as low as 11lbs on "street cars"..

i was told 13 is as low as you want to go, any lighter, and the car becomes hard to drive around..

mine will be rather harsh anyways though.. KEP stage II + springless 4 puck disk..

Va914 · 02-01-2002, 09:46 AM

What does the stock Flywheel weigh, 18#'s?

If I am running stock engine with the D-jet , should I take some lb's off the flywheel?

Thanks

jabez · 02-01-2002, 10:08 AM

Jake says not to lighten, but I had already cut mine down to 12 lbs. I get instant acceleration and no stall when I lift off the gas at high RPM (that is what lightening them too much causes).

GS

Va914 · 02-04-2002, 11:49 AM

Does anyone have the depth the friction surface of the flywheel is from the pressure plate mounting surface?

Also, what is the thickness of a good reusable friction disk? I have removed a clutch assembly, miles unknown, and the whole assembly looks to be in good condition. Tom's book uses the 7mm wrench test.
If I can a summer or two out of this clutch, that would be great.

Thanks

Kerry

Otto · 02-07-2002, 06:27 PM

The distance between the mating surface of the pressure plate and the surface of the flywheel is called the register. The register for 914s and 914/6 with the push clutch is 22.5mm. The wear tolerance for the clutch disc is8.0 7.8.... You don't want to run a lightened flywheel because your car will be slower. We did this in 1974 with our Showroom Stock A Class SCCA car at Riverside. I ran ten laps and did a time average per lap. We then changed to a lightened flywheel and went three seconds a lap SLOWER!!!!!!!! It seemed that the reciprocating mass of the heavier flywheel pulled us though the esses with more speed. OTTO

JP Noonan · 02-07-2002, 07:24 PM

Va914 there is a saying "penny wise, pound foolish". If you are doing the work yourself then just make sure there is some meat left on the disc so the rivets won't get hit and either kill the flywheel or explode the clutch. If someone else is doing it, then a new disc is cheap compared to the install.

I ground my own flywheel at a "big block" NAPA (my friend only did one 911 motor in about 15 years, and that was for the old owner). I used a liquid cooled flywheel grinder with a cup shaped stone. Just make sure you remove the same amount of material from the step as you do from the face. Use Otto's measurements to make sure that the disc won't slip and also that the disc dosen't hit the flywheel bolts.

I've seen people grind down the bolts after the FW is torqued down, but that seems kinda red-neck engineered to me.