tlawso04

I wanted to see whether anyone can tell me what might be the problem when I release the clutch rapidly at high RPM's the clutch does not immediately engage? It does shift smoothly into all gears including reverse. It feels like it is slipping. Thanks

James Bailey

It is slipping.......

leadfoot

A slipping clutch sucks. Completly kills all the fun. Check the ball cup bushing on the clutch arm. If very worn or has pieces missing proper alignment can be affected causing only partial engagement of the flywheel/disk surfaces

My 87 had this condtion. Bought a clutch kit and related parts first which i installed after having the flywheel turned. The old clutch had some meat left on the disk but glazing on both surfaces about an inch wide was apparent.

l have speculated that just the bushing being replaced may have lessened or possibly eliminated the slippage for some amount of time. Might want to make sure the clutch rod linkage is adjusted properly too

Some think you can light up the tires, but in a straight pull with sticky 265s the clutch will probably fry first. I have to think automatics do better burnouts due to torque multiplication. Never had chance to drive one w a kickdown sw

Rich P

blown 87

You have to be kidding.

James Bailey

First off the 928 is NOT a drag race car. Secondly if you slip the clutch while engaging it quickly hot spots the fly wheel and abuses the friction discs making it far more prone to slip the next time you dump the clutch.
It is just not what it was designed to do. Make your "races" from 50-150 mph or plan on replacing lots of clutch parts.

dprantl

Maybe the later single-disc clutch may have issues, but the dual-disc clutch in working condition doesn't have any problems with quick engagement at high RPM. And an auto does better burnouts?

Dan
'91 928GT S/C 475hp/460lb.ft

blown 87

Mine does not either, will spin the heck out of 295 all the way through first, and I bet your blown 91 will do it at will

87 Shark

You may want to check you're brake fluid. When was it last changed? The clutch slave draws fluid from the brake reservoir. When i replaced my fluid and cleaned and bled the system including the clutch slave ( and got rid of all the crap that the PO let build up in there) the clutch locked up like new. Porsche recomends this be done every 2 years and more often if the car is tracked.

dprantl

The clutch hydraulic system should not have any effect on how well the clutch holds power (unless it is somehow leaking inside the clutch assembly). That is entirely up to the friction discs and pressure plate/intermediate plate. The hydraulics could cause shifting problems and/or clutch dragging issues.

Dan
'91 928GT S/C 475hp/460lb.ft

87 Shark

Just asking when this was done. I'm shure this is overlooked. My 87 5speed felt totally different afterthe fuid change. I was shocked to see the crap that came out. I'm shure it prevented the hydraulics from working properly. It's an easy check and needs doing regularly.

James Bailey

It is possible that there were some air in the system and bleeding it may have removed it....but as mentioned it would only change how it disengages and not how we it locks up.

And yes it is good to change out the brake fluid every two years.....