suprasupra;1745608 said:
I am having the exact same problem as the original thread starter with my 87 turbo with w58 swap. I have the clutchmasters stage 2 disc and pressure plate with a freshly machined stock flywheel including the step and properly adjusted freeplay. Has anyone had this problem and actually resolved it? I'm thinking that the disc and pressure plate are just junk, what else could it be?
The kevlar full faced discs are super sensitive to proper break-in. You NEED to take it easy on it for the break in, or you will ruin it. If you take it easy on it now, it may recover... but it may not. If it keeps slipping, you don't need to replace the pressure plate, just the disc. Either run a carbon ceramic 6 puck sprung hub disc (spec, ACT, comp clutch, whatever..) or use a stock style disc. The stock style disc will hold plenty of power, and will help prevent your W58 from grenading. I'm running a stock disc with a comp clutch stage 4 PP behind my 1JZ and it's holding up, but it doesn't like repeated launches... I had it smoking once, but it recovered after a few days of taking it easy.
To the OP: Assuming your pressure plate bolts aren't falling out. I agree it could be a bad flywheel step. The result of incorrect step is that it moves the pressure plate past it's ideal operating range and results in a sharp dropoff of clamping force. It's the same thing that causes a clutch to start slipping for no apparent reason right before the disc wears into the rivets. There used to be an article on the ACT website about this, not sure if it's still there or not. It requires a pretty huge screwup in the step to cause much of a problem though. I'd also check for binding on the collar that the release bearing rides on, and for any binding on any of the release system parts. It could also be the pressure plate itself is defective (binding or weak), but that's really rare.
Personally.. despite the warnings of proper break in on ceramic metallic discs... I've never done it. The paperwork that came with the very first ACT 6-puck disc I ever bought, back in 2002, said there was no break-in required. It also said that the properties of the disc were that if it did heat up from slipping, that it would grip even harder (and that was the case, if you tried to slip it more than a little, it would just grab harder and either break something or GO). I beat on that clutch from day one and it lasted over 100K miles. Organic and kevlar discs are another story, they need a break-in for the resin that holds the fibers together to properly cure.
