spanky

My 87 951 original clutch finally gave up the ghost last week after 143,00 miles. Job well done. Now that its time to replace it Im wondering if there are any other stock Porsche model clutch kits that can be fitted on to a 951 with out any modification what so ever that will work just as well or better or should I play it safe and replace it with a new Sach stock 951 clutch. Thanks in advance.

Tom M'Guinn

Unless you have more than around 310-320rwhp, I'd just use the stock pressure plate, factory cup disk, and factory flywheel. (The cup disk eliminates the little helper springs that tend to break and ruin the clutch.) Paragon has nice kits ready to go, among others. If you have more power, then I'd suggest still using the cup disk and just increasing the pressure plate clamp force -- either with the KEP 1 Pressure plate or with a re-sprung factory pressure plate.

I use the KEP1 and the pedal pressure is stiffer, but it's not bad, and it holds 500rwhp. You can check out mine if interested. Southbend Clutches and others can also modify a factory pressure plate to give it more clamp -- which ends up somewhere between stock and the KEP1, so not a bad compromise for motors in the 300-400rwhp range. If you stick with the cup disk, factory flywheel and KEP or factory pressure plate, you'll retain factory-smooth engagement without shutter/chatter, which is not something you can say about most performances clutches for these cars. Ask me how I know....

Humboldtgrin

930

spanky

930. Pls explain!

Tom M'Guinn

He's suggesting you use the a 930 clutch disk instead of the cup. Lots of people do that, and it works well -- similar to the cup disk. Paragon can set you up with that too. Some people have clearance problems with that disk, which seems to be a function of the thrust bearing wear in your motor. There's also some cheap knock-offs worth avoiding. I just suggest the 951 cup disk to avoid those potential problems, and it works great, but if you get the original 930 disk and not the eBay knock-off, and if your engine doesn't have excessive end play, the 930 disk is a similar option to the cup disk.

Voith

How do you do that? New center steel spring piece or some other trick?

Tom M'Guinn

They change the fulcrum point.

GPA951s

Agree, Stay stock or thereabouts.. DO NOT get anything over a stage 2 if you go the spec route... Chatter on a performance clutch stinks, It makes you look like a novice leaving a light no matter what you do and if you miss the revs downshifting even a bit it will vibrate your car so hard that your rear view mirror will fall off.. Then the car goes on "the top rack" because its annoying to drive..IF you get an alu Flywheel, Well lets just say you wife or GF wont enjoy diving it either.. :-)

Tom M'Guinn

Exactly. To me it just takes all the fun out of driving the car, when you chatter and buck away from every stop. That is generally a function of the clutch lining material, so if you stick with the stock material -- like a cup disk -- and add clamp force, you can have a perfectly smooth clutch that holds more power. That said, if the first clutch lasted 143k miles, it sounds like the bone stock parts (with cup disk rather than the original with the helper springs) are the way to go on this car.

Laust Pedersen

One detail on the clutch disks I have not seen mentioned, which affects the propensity for chatter, is its compression compliance. Take a look at the attached picture, which shows an OE disk. It has wavy sheet metal acting as a spring between the two linings to cushion the engagement.



Last Summer I installed a (claimed) 930 disk, which has much harder (very short 10% to 90%) engagement and requires a "well trained" left foot to avoid chatter. As a result it also does not match the pedal helper spring's characteristics, so it requires 5-10 lbs more effort.

For a daily driver with OE torque and no “drop clutch” starts (saving the small springs), I would go for the OE disk.

SummitP

My car runs a k26/8 turbo, and I run around 14-15psi,and I recently completed a kep pp and cup disk install. Could not be happier. Smooth engagement, clutch pedal is heavier, but still very easy. Could not be happier.

Jherriott

Can anyone tell me where to buy the KEP 1 pressure plate and cup disc. Is there a vendor that supplies everything needed in a kit?

Jase.

gruhsy

http://www.patrickmotorsports.com/


http://www.patrickmotorsports.com/pa...ission-clutch/

directly from KEP https://www.kennedyeng.com/clutches

rlm328

I got mine directly from KEP. Call them up tell them your application and they will steer you in the proper direction.

lart951

Kep stage 1 + 930 disc, for anything under 500rwhp is fine.