Well I finished the Procharger up and got a chance to play around with it for a few weeks and my clutch just exploded the other day. Pretty sure it is disintegrated.....

I will post pics soon but was wondering what an all around good clutch would be for the $$ and Strength, Streetability Ect. I was looking into a Spec Stage3+ that holds 842ft lbs. Any opinions or hands on experience? I wanna hold at least 800 ft lbs tq. Thanks!!!

 

I can't see what the car ran and you didn't say what kind of power it's putting down but I have run 11.0's@128mph with a 1.77 60ft in my 92 street car on MT 315/35R17 radials using a regular SPEC Stage 3 which is a 6 puck sprung hub style disk.

I want to caution you about using "too much" clutch in a C4 Corvette. Honestly what I have is too much clutch IMO.... I have what I have because back in the day I didn't know any better... After 4 years with my 92 and this engine I've learned alot and it's been an expensive education. I like the SPEC Stage 3 but it's very unforgiving.

These bad *** street clutches lock up and hit the driveline like a ton of bricks... With traction you can break something in the rear end with just a little bit of power. You really have to drive these clutches off the line by slipping them... or by just rolling the car out of the gate off idle.... then you need to be careful about the 2nd gear shift.

Over the past 4 years, I have destroyed 2 D44HDs in my 92 and a number of halfshafts and halfshaft U-Joints by getting greedy with the launch on a good track prep day. I've only made about 125 passes in the car and driven it about 10,000 miles with this engine in 4yrs time because for a while it was broken after every track outing.

I honestly have plans to detune it and install a SPEC Stage 2+ clutch in it. Been busy with campaining my real race car this year so the 92 is relegated to weekend street driving and no more track days.

So basically you have 2 choices.

1) Run a bad *** clutch and be easy on it off the line and on gear changes.
2) Run a soft hitting clutch and know your gonna eventually over HP it and have to replace it.

Will

 

I can write a book about the c4 zf6 clutch.

Ive been running spec stage 3+ clutch. Im happy with that product. I recently installed another one (one of the springs broke out - prob due to gear noise, which I corrected with thicker countershaft shim from zfdoc).
Great bite and very streetable.

I broke the center out of a spec stage 2 'kevlar' clutch and needed a tow home back in 2006. So dont use that one. Other than that I liked the clutch.

Some of the 'puck type' cluches (i think spec stage 3 is one) ive heard can be a real handful. They either grab or dont. Its tough to slip it off the line.

You want a 'spung hub' type clutch. Sprung hub dampens gear noise and driveline shock (to some extent - its still very possible to exceed what a sprung hub can dampen).

Dont believe all the BS thats out there. SPEC is makng a good product.
As for driveline shock...you want a sprung hub type clutch.

Get rid of the dual mass if you havent already. Its a heavy PO$ better suited as a boat anchor.

i recommend the alum. flywheel.

THe noise everyone talks about is not from the flywheel, its from the transmission. So if you have 'noise' then put in a thicker countershaft shim (zfdoc).

The thcker countershaft shim eliminated my trans noise that I had been told (incorrectly) is a consequnce of the alum. flywheel. Turns out the noise shouldnt be there, just that it is better masked by the dual-mass flywheel.

 

I installed a Stage 3 plus clutch with a Spec lite weight billet steel flywheel in my 96 and am very happy...drove it for a year...I drive mostly street / commute with some driving in the Sierra Nevada twisties; my wife drove it as much or more than I, and her driving style, should we say is "enthusiastic" ? long story short, recently pulled the engine, tore down the clutch and it looked as good as it did when initially installed.

for what its worth here's what my clutch job entailed:

good used C beam (torque arm) Dino's corvette salvage: $150
Spec Stage 3 plus clutch, SC423YF: $619
Spec flywheel SC05S: $299
roller pin style pilot bearing, Summit: $13.49
Throw out bearing (GM) Ecklers 50583: $89.99
flywheel bolts, Summit: $14.75
rear crank shaft seal, NAPA: ?
rear transmission tailshaft seal, NAPA: $12
modify shifter ZFdoc: $165
rebuild shifter assembly, ZFdoc: $45
heavy duty tailshaft housing bushing, ZFdoc: $40
beam plates, fabbed my own: N/C
clutch fork VintageParts 10085210: $141.62
clutch fork mounting ball stud, VintageParts 10227809: $44.09
retainer, clutch release bearing collar, VintageParts 10111569: $13.49

also, replaced clutch master cylinder and clutch slave cylinder.

A further note, to get adequate throw on the clutch pedal to displace sufficient fluid to allow proper throwout bearing travel (0.250 to 0.315 inch per ZFdoc) I had to replace the thick spacer between the clutch master cylinder and the firewall with one approximately half as thick.

 

Interesting... wish I'd know about that when my tranny was out a couple weeks ago because my ol' McLeod street twin & alum flywheel combo is hella loud and hits like a mack truck!!

 

I have a P-1SC Procharger also and I'm running the lightweight SPEC flywheel and stage 3 sprung hub clutch with an LT-4 pressure plate. I also have installed the shim as mentioned above. However, I do have the rocks in a can sound in neutral, but it's tolerable since I've don't know what a stock setup sounds or feels like. Over the winter I converted from an auto to manual and love it. Jim at power torque systems hooked me up with all the clutch components. So for my application the above was recommended. I've also never had a manual car so to me this setup is street able and I assume would be track worthy. I've already spun first to third and have had any damage, but only time will tell. I also plan on running more boost very soon so I'll report back if my setup doesn't hold up.

 

You guys with the stage 3...does it have a sprung hub or not?

Spec stage 3+ is actually going to be a more streetable clutch than stage 3.

Its full friction disk with a sprung hub.

I still have a light rapping sound at neutral, but all the driving noises are gone with the shim installed.

Btw. I'm not always a fan of all of jim's advice. I'm not sure where he gets his strong opinions from but he's really bad mouthing some of our supporting vendors.


There might be some truth to some of it, but not 'the sky is falling' chicken-little like he claims.