I've been working on getting everything dialed in for a 10 second pass on the stock long block. I just recently purchased hp tuners and a wideband and have made some progress on tuning.

I had planned to go to Dallas this weekend and was doing an oil change Thursday night and found this:



Close Up


This is a piece of the clutch disk that decided it wanted to see the light of day after 10,000 miles. Has anyone experienced this type of failure? The clutch still engages, so I think I caught it early.

What should I expect to find upon teardown?

Any recommendations on the next clutch?

 

wow which clutch was that? Lucky it did not come apart at 6k RPMs.

 

Ouch! A blowproof bell is needed for a 10sec ride, there's the proof. Sucks to have the setback, but glad you found it.

 

If that is part of your clutch, no way in hell would I be driving the car any further until it has been taken apart and inspected.

If one piece has already let go, it could be well out of balance, and when will the rest let go ?

And more to the point, what clutch is it ? I know I wouldnt want to be using it on my car !!

 

Yes, I agree it is a setback, but after seeing this I have no choice but to install a scatter shield as part of the repair. I plan to go with the Quick Time brand.

The car is down right now. It will not see anymore action until it is repaired.

The clutch is a SPEC 3+ that was installed Summer of '08 and has right at 10,000 miles on it. IT was professionally installed by a well-known shop. The car has put down 560 hp and 600 tq. The clutch has not been used beyond its rated capacity and was holding fine until I made this discovery.

So far in my research, I have found pictures of the clutch hub with the metal around the springs fatigued and the the springs themselves broken and ground up by the flywheel or pressure plate. Also, the rivets have usually sheared off or come loose.

If I find that this is the case, this will be sent back to SPEC for a replacement. There is no reason that these type of defects should occur when a clutch is used as intended.

As stated, the clutch never slipped. There is now a piece of it sticking out of the bellhousing. The material looks very much like a part of the hub to me. A full tear down with pictures and findings will follow when I get the time. This is an unplanned repair that will have to be worked into the schedule and budget.

 

You will probably find a broken strap connecting the floating plate(part of the pressure plate) to the cover .Hard launches tend to collapse the straps,causing them to buckle and snap,just like what you saw.QT shield and a GOOD quality aftermarket clutch,perhaps even a twin depending on your wants/needs should take care of everything.

 

Thanks for the reply.

I am open to suggestions on a GOOD quality aftermarket clutch.

Right now I am sitting on 11.20 @ 128 with a 1.70 60' in the heat (1700 DA).

The plan is to make more power and go faster as time goes by.

 

I think I have seen good and bad with them all. Get a spec, mcleod, or RPS twin and hope for the best. Make sure to measure clearances.

 

Thanks, is this in regard to shims? I may get your help in checking clearances when the time comes or at least give you a call.

 

When I buy a clutch, I certainly wouldnt want to hope for the best !!

I'd simply want it to work.


For me Textralia has worked faultlessly for some 5 years. First an OZ700, and then their triple. I didnt need the triple, I just wanted it.

 

Any other opinions on reliable clutches that don't come apart when used to transfer the power over and over? I realize that the friction surface will eventually wear out with repeated use, but coming apart after using it below rated capacity...

 

Have you experienced something similar? I'm trying to learn something so that this isn't repeated.

Are there certain clutches that don't have this design flaw or is this a possibility with every clutch? I've come across issues before where a manufacturer will rate something at a certain level but fail to mention that there is one part that may or may not be able to handle the stress.

I understand very well that you have to pay to play. In this case, I tried to match the clutch with my power level and intended use. Now it's time to try again and I am looking for recommendations on what works.

 

That's an eye opener

 

That's certainly not a ringing endorsement for Spec clutches. Should not have failed at all, let alone catastrophically.

 

I have replaced several broken clutches with that problem,SPEC is no more or less susceptible than any other(with a strap mounted floater plate)in my opinion. I personally run a tex twin and although it has over 100 passes(probably more) it has performed flawlessly with only the need for a friction disc replacement.It does have a little noise at idle(floater rattle due to NO straps) I would NOT rule out another brand due to this design as it does make for a quiet clutch setup.RPS,Mcleod,ACT all make good quality HP clutches for your setup,I would call those companies tech lines and speak with them personally about your setup. Best of luck,and dont forget the QT scattershield as well as a remote bleeder kit !

 

Hi, give me a call tomorrow and we will give you a pacakge deal on all the items you need to do it right!!! We sell the best of the best when it comes to driveline products...Plus we keep almost everything instock at all times..thanks

 

Thanks for the insight. The QT bell will be purchased. I have a remote bleeder sitting on the shelf, a Z06 torque tube and a new LS6 slave waiting to be used The master cylinder was just replaced a couple of months ago. Now its time to pick a clutch and get down to business.

 

Thanks Mike. I ordered a remote bleeder, torque tube bushings, etc. from you earlier in the year. I'll call you tomorrow and discuss a clutch package and scatter shield. Thanks for stepping in.

Does anyone know if the downpipes have to be removed to do the clutch swap? They weren't very fun to install.

I may become a member of the jackstand clutch swap club before long.

 

Your setup is a little different, but on mine every damn thing behind the engine comes down, AND I had to back the headers off.

 

I'm guessing that you loosened the longtubes for side to side clearance? I think my downpipes exit right about where a collector would fall. So, I may have to remove them.

Did you remove the bell housing or just do the clutch swap through the bottom part of the bell? I'll have to remove mine anyway for scattershield.