Possible clutch replacement
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From: USVI
Originally Posted by Kevin
This will be interesting!!
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From: Westlake Village, Ca. Lake Tahoe, Ca.
Interestng that you mention that Jason. The clutch disc you have pictured looks like mine used to. When I dropped it off at CM and discussed the issues of slipping and amount of HP/torque the clutch required, they looked at the disc and said they were not surprised at it's failing. I did notice the difference in friction material that you point out and I would like to know if anyone here has experience with them. I certainly am no expert on clutches and have to trust these guys as they build high performance clutches daily. Thanks
Originally Posted by JasonAndreas
Does the amount of friction material on the disc control the on and off nature of the clutch? The Clutchmaster disc doesn't look to have very much compared to a regular factory unit.
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From: Gulf of America-Pacific NW
Jason, the diameter of the blue springs absorb the energy/shock. Different disks have larger springs. This setup will be like a On/Off light switch.. The other problem is material was taken off two critical places. One being the surfaced flywheel, the other being the actual re-built pressure plate.. The pedal in this application will be right at the top..
And with the metal ceramic disk this system will cause most guys to want to sell there cars.. Which has actually happened.. Woodster had this clutch..
EDIT: Scott the problem with your original clutch is you were sold a RS lightweight clutch which was used in a 964 RS or 993RS.. There is no way in this world that it would hold a 993TT that had uprated turbo's let alone a 3.8ltr engine. The intent might have been good. It was NOT a GT2 setup.. Maybe a NA 911 that ran in a PCA GT2 class.. The 996 GT2 has a solid center with no springs.. Many people make the mistake and use that with a lightweight flywheel.. You can't do that either..
And with the metal ceramic disk this system will cause most guys to want to sell there cars.. Which has actually happened.. Woodster had this clutch..
EDIT: Scott the problem with your original clutch is you were sold a RS lightweight clutch which was used in a 964 RS or 993RS.. There is no way in this world that it would hold a 993TT that had uprated turbo's let alone a 3.8ltr engine. The intent might have been good. It was NOT a GT2 setup.. Maybe a NA 911 that ran in a PCA GT2 class.. The 996 GT2 has a solid center with no springs.. Many people make the mistake and use that with a lightweight flywheel.. You can't do that either..
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From: Westlake Village, Ca. Lake Tahoe, Ca.
All good info and I appreciate it.
As far as the re-surfaced flywheel and pressure plate, the surface could have been cleaned up with as little as .001 removed so that is an assumption that the pedal will be right at the top. My C4S had a new factory clutch in it and the pedal was at the top, so who knows.
I was not sold any clutch, this is the clutch that was in the car when I bought it.
The previous owner had it installed and I am trying to rectify it
I will address the clutch disc.
Thanks again
As far as the re-surfaced flywheel and pressure plate, the surface could have been cleaned up with as little as .001 removed so that is an assumption that the pedal will be right at the top. My C4S had a new factory clutch in it and the pedal was at the top, so who knows.
I was not sold any clutch, this is the clutch that was in the car when I bought it.
The previous owner had it installed and I am trying to rectify it
I will address the clutch disc.
Thanks again
Originally Posted by Kevin
Jason, the diameter of the blue springs absorb the energy/shock. Different disks have larger springs. This setup will be like a On/Off light switch.. The other problem is material was taken off two critical places. One being the surfaced flywheel, the other being the actual re-built pressure plate.. The pedal in this application will be right at the top..
And with the metal ceramic disk this system will cause most guys to want to sell there cars.. Which has actually happened.. Woodster had this clutch..
EDIT: Scott the problem with your original clutch is you were sold a RS lightweight clutch which was used in a 964 RS or 993RS.. There is no way in this world that it would hold a 993TT that had uprated turbo's let alone a 3.8ltr engine. The intent might have been good. It was NOT a GT2 setup.. Maybe a NA 911 that ran in a PCA GT2 class.. The 996 GT2 has a solid center with no springs.. Many people make the mistake and use that with a lightweight flywheel.. You can't do that either..
And with the metal ceramic disk this system will cause most guys to want to sell there cars.. Which has actually happened.. Woodster had this clutch..
EDIT: Scott the problem with your original clutch is you were sold a RS lightweight clutch which was used in a 964 RS or 993RS.. There is no way in this world that it would hold a 993TT that had uprated turbo's let alone a 3.8ltr engine. The intent might have been good. It was NOT a GT2 setup.. Maybe a NA 911 that ran in a PCA GT2 class.. The 996 GT2 has a solid center with no springs.. Many people make the mistake and use that with a lightweight flywheel.. You can't do that either..
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From: Orange Park Acres, CA
[QUOTE=Kevin]And with the metal ceramic disk this system will cause most guys to want to sell there cars.. Which has actually happened.. Woodster had this clutch..
Agree, this is a racing disc and NOT good on the street.
BTW, I have used this disc for racing which is ok but not on the street.
I've used the 993 GT2 disc which I believe is a RS part, and it works fine with the upgraded pressure plate. I haven't had the clutch engagement problems Kevin has refered in spite of having my flywheel resurfaced.
Jimmy
Agree, this is a racing disc and NOT good on the street.
BTW, I have used this disc for racing which is ok but not on the street.I've used the 993 GT2 disc which I believe is a RS part, and it works fine with the upgraded pressure plate. I haven't had the clutch engagement problems Kevin has refered in spite of having my flywheel resurfaced.
Jimmy
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From: Gulf of America-Pacific NW
I will try to snag a picture of a 996GT2 clutch disk but it has "NO" center springs.. This allows no dampening to the clutch system.. It can be used with a Dual Mass Flywheel which the 996GT2 has.. It is not recommended for a "street application" when one ditches the dual mass flywheel and you run a solid lightweight flywheel.
I did not say that you will get engagement problems when you resurface the flywheel.. What I said was "The other problem is material was taken off two critical places. One being the surfaced flywheel, the other being the actual re-built pressure plate" Taking metal from both surfaces does not work in the long run. Why because your clutch disk will wear.. The rod on the slave cylinder doesn't have enough travel to account for 3 short stacked surfaces.
It is not possible that you can clean up a smoked-burnt flywheel and pressure-plate at .001" That's half a human hair.. And "yes" when you have both surfaces machines with metal removed, the pedal is at the top and your engagement with the Power assist (which your C4 didn't have) will be limited.. It's not fun on the 405 at rush hour..
The better recommendation is to sell these parts, and purchase a Sachs Race Pressure plate (new) and have ClutchMaster beef it up if you want (not needed at your HP level).. Then purchase the new GT3RS clutch disk (not the 996GT2 Disk)and you will be off to the races.. Rebuilding Normally Aspirated Clutch packs have less than favorable results in the long run.
I did not say that you will get engagement problems when you resurface the flywheel.. What I said was "The other problem is material was taken off two critical places. One being the surfaced flywheel, the other being the actual re-built pressure plate" Taking metal from both surfaces does not work in the long run. Why because your clutch disk will wear.. The rod on the slave cylinder doesn't have enough travel to account for 3 short stacked surfaces.
It is not possible that you can clean up a smoked-burnt flywheel and pressure-plate at .001" That's half a human hair.. And "yes" when you have both surfaces machines with metal removed, the pedal is at the top and your engagement with the Power assist (which your C4 didn't have) will be limited.. It's not fun on the 405 at rush hour..
The better recommendation is to sell these parts, and purchase a Sachs Race Pressure plate (new) and have ClutchMaster beef it up if you want (not needed at your HP level).. Then purchase the new GT3RS clutch disk (not the 996GT2 Disk)and you will be off to the races.. Rebuilding Normally Aspirated Clutch packs have less than favorable results in the long run.
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