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@!&_)*(^% clutch again!!!!!

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Old 03-23-2008 | 11:03 PM
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Default @!&_)*(^% clutch again!!!!!

Well the new power from the SC trashed my stock clutch, and after much deliberating, and advice from our friend Jim Bailey, I decided the GTS clutch upgrade would be fine. So I buy this clutch and it is trashed after only 1500 miles. I do not beat on the car too much meaning no drag launches. This thing was 1200.00 bucks and its got me little warm that its fried already.
I don't know what clutch will hold. Everybody kept saying dont go with the GTS unit , get a spec 3 or equivilant. WTF.

sorry for the rant, but this sucks big-time:
Kevin
Old 03-23-2008 | 11:07 PM
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Whats a Spec 3?

As for the new clutch being trashed. Do you mean trashed as in it doesn't hold and your slipping. Or have you actually pulled the lower cover off and see the disc surface is heavily worn already?

1500 miles is really insane, i don't know what the typical life out of a 928 clutch is because i haven't owned mine long enough to go through one, but I imagine it to be anywhere from 30,000-60,000 miles.
Old 03-23-2008 | 11:14 PM
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Ryan it is slipping like an octopus on iceskates bro. It glazed badly.
Old 03-23-2008 | 11:18 PM
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I would say the pressure plate then is the the problem, maybe its defective. If that thing slips then yeah its going to eat right through that disc in no time. But I dont really know how a PP is defective, its really just a spring.

Was the slip a real problem with the old clutch as well? Or was the previous clutch replaced because of a normal wear interval had elapsed?

Dont tell me those Murf's are making THAT MUCH power?

Or could your clutch pedal be out of adjustment and the rod not be set properly so that when the clutch pedal is released the PP may not be fully released? I would check that out. Does your clutch disengage very shortly after you touch the pedal? I think I have mine set about midway or between midway and bottoming out the pedal before it releases. If the old clutch was doing this as well then I would suspect something with the clutch adjustment.
Old 03-23-2008 | 11:31 PM
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Ryan every part of the system is new and spec'd by the book. I am very thorough in my repairs. The clutch disengages as it should with the proper freeplay at the rod. The GTS clutch is a very stout and heavily sprung unit and I do not suspect it.The old stock clutch was 10k miles old and fried the 2nd day the Murf kit was installed. I had the flywheel turned and the GTS kit went in. Now the disc as well as the flywheel (hot spots all over it) are trashed. And yes the Murf kits ARE that powerful.
Old 03-23-2008 | 11:33 PM
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well i see only one solution

take that stupid thing off and send it to me, let me deal with it
Old 03-23-2008 | 11:44 PM
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Originally Posted by RyanPerrella
well i see only one solution

take that stupid thing off and send it to me, let me deal with it
You want the old clutch??? HaHaHa!
Old 03-23-2008 | 11:51 PM
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Dejavu... I have a GTS clutch in my garage too. I went to a Spec Stage 3+. It took a long time to bed in, but it did finally after an hour of Chicago stop and go traffic.
Old 03-23-2008 | 11:51 PM
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Originally Posted by Kevin Michael
Ryan every part of the system is new and spec'd by the book. I am very thorough in my repairs. The clutch disengages as it should with the proper freeplay at the rod. The GTS clutch is a very stout and heavily sprung unit and I do not suspect it.The old stock clutch was 10k miles old and fried the 2nd day the Murf kit was installed. I had the flywheel turned and the GTS kit went in. Now the disc as well as the flywheel (hot spots all over it) are trashed. And yes the Murf kits ARE that powerful.

I am willing to bet that turning the flywheel is part, if not all of the problem.

I refuse to turn or install turned flywheels at my shop any more, I have learned that lesson the hard ($$$$) way.

I do not have a concrete reason for the failures I have seen, just some thoughts and ideas on it.

Greg Nettles
Old 03-23-2008 | 11:55 PM
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is it possible you let the cluch slip too much while you drive the car, This would be one way to cook the PP springs IE lots of clutch slippage and giving it gas while its still taking up.
To damage 2 seperate clutch systems tells me there is something else wrong either a mechanical defect or a pilot induced failure.
So lets see , you said the whole system is new does that go for the clutch master and slave? Was the Flywheel cut correctly?
Is the throw out bearing new and did you fill the gap on the inside of the TOB with grease( the part that runs on the guide tube).And do you have the correct TOB on the correct release arm?
Is the slave cylinder the correct part IE is the pushrod the correct length?
Is the clutch pedal reduction pressure spring adjusted correctly.?
Did you install a new splined short shaft and use some sore of HI temp grease on it so the disc wont catch on the splines?
These are just a few thoughts I have , I hope that you can atleast find that somethings not right, this shouldnt happen, unless the clutch is slipping. Or there might be air in the lines. So replace the clutch and remove the whole clutch system and bleed it on the the bench this will remove all of the air before you start.
Do a search for another way to bleed the clutch by Mrmerlin, this is really the best way to insure a airless clutch system and in the long run it will save you time and its pretty easy to do, Goodluck.
Old 03-23-2008 | 11:57 PM
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Blown 87, Tell us more......
Old 03-24-2008 | 12:03 AM
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Originally Posted by Mrmerlin
is it possible you let the cluch slip too much while you drive the car, This would be one way to cook the PP springs IE lots of clutch slippage and giving it gas while its still taking up.
To damage 2 seperate clutch systems tells me there is something else wrong either a mechanical defect or a pilot induced failure.
So lets see , you said the whole system is new does that go for the clutch master and slave? Was the Flywheel cut correctly?
Is the throw out bearing new and did you fill the gap on the inside of the TOB with grease( the part that runs on the guide tube).And do you have the correct TOB on the correct release arm?
Is the slave cylinder the correct part IE is the pushrod the correct length?
Is the clutch pedal reduction pressure spring adjusted correctly.?
Did you install a new splined short shaft and use some sore of HI temp grease on it so the disc wont catch on the splines?
These are just a few thoughts I have , I hope that you can atleast find that somethings not right, this shouldnt happen, unless the clutch is slipping. Or there might be air in the lines. So replace the clutch and remove the whole clutch system and bleed it on the the bench this will remove all of the air before you start.
Do a search for another way to bleed the clutch by Mrmerlin, this is really the best way to insure a airless clutch system and in the long run it will save you time and its pretty easy to do, Goodluck.
Stan, everybody I know of that has SC'D their sharks have had this issue exactly. Andrew Olsen PM'd me on this and said do not buy the gts clutch get spec 3 . Anybody got a good flywheel or spec 3 disc for sale?
Old 03-24-2008 | 12:13 AM
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Originally Posted by Kevin Michael
Stan, everybody I know of that has SC'D their sharks have had this issue exactly. Andrew Olsen PM'd me on this and said do not buy the gts clutch get spec 3 . Anybody got a good flywheel or spec 3 disc for sale?
Then I guess it might not have been the flywheel being turned, in this case.
I still would not turn one.

So does that mean that ANY 928 stock clutch set-up is not strong enough?
Or is it just the GTS ones?
Old 03-24-2008 | 12:19 AM
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The GTS is the strongest stock single disk set up available. Some of the OB sc'd 928's dual disc clutches hold up fine, but then they are not producing anywhere near the power of the late SC'D cars.
Old 03-24-2008 | 12:20 AM
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GT clutches are definitely too weak for for any SCer application.

GTS did not work fro me, but I had not re-surfaced the flywheels, so I cannot say the PP was the issue, plus I think my RMS may still be leaking slightly.

The Spec Stage 3/3+ has a very aggressive friction disc. You might just try getting the Spec friction alone and trying that.

The other option is to use the dual-disk clutch setup, but I'm not sure how easy/affordable that is.


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