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Full Version: Flywheel resurface and clutch disc confusion
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jjs3rd914
I have read all the threads on the key dimensions and do believe my flywheel is toast. The bolt heads were found to be shaved and upon measuring the"c" distance was found to be 8mm where the minimum is stated is 11.00. ("c" = the distance from the disc surface to the bolt circle surface). Also the "a" distance is more the the 22.5mm which must be retained during a regrind. It appears that a previous surface ground only addressed the disc surface and did not shave the PP surface a like amount.

Now the question? I believe I read that the 11.00mm minimum was for a 4 spring clutch disc only and that installing a 6 spring disc (911) the 11.00 is no longer an issue. I would like to have this flywheel regrind to spec maintaining the 22.5 mm, but by doing so would decrease the "c" dimension even more. I want to replace the shaved bolts with the thicker new ones. Can this be done? Will there be enough clearance between the disc and the bolts? Is the 11.00mm true for the 6 spring disc or does a lesser minimum apply, if so what is that (with new bolts)? Tell me I do not have to get a new flywheel?

Thanks
Jeff
So.Cal.914
Just get a good used one, you could end up spending more trying to Frankenstien

it.
jjs3rd914
I have taken a closer look at the flywheel. The "a" dimension is only about 1mm more than the 22.5mm nominal so it is possibly due only to wear. What is still confusing is it seems like there is plenty of clearance to install new bolts with a new six spring disc. As mentioned the as found "c" measuremt is 8mm which is far less than the 11mm minimum. Yet when I lay a new six spring disc on the flywheel with full size bolts and the large washer there seems to be a lot of clearance remaining even taking in allowance for disc wear. We checked this by pushing up on the bolts from the back side of the flywheel.

Am I missing something here? I do not understand the 11mm published minimum. I have checked with a supplier of resurfaced flywheels and they measured the "c" dimension at 7.5mm. What gives? Is the 11mm wrong?

Maybe the flywheel has life yet.

Thanks,

Jeff
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