Carrera GT 12 year engine out service (pic heavy)
Discussion
lowndes said:
993rsr said:
The clutch is very interesting. It was the first attempt at a carbon ceramic clutch in a production car (PCCC, Porsche Ceramic Composite Clutch).
The beauty of this is not only is it very compact (6 1/4" in diameter) allowing the engine to be located lower in the car than a traditional clutch getting the mass lower in the chassis, but it is extremely light meaning the engine revs with seemingly little inertia due to the lower rotational mass compared to a conventional clutch - 10 times less.
Used correctly they are very durable, and it's worth overcoming the aggravation of become conversant (I saw it as a challenge to master, rather than a problem) with it for the benefits offered.
The thing that intrigues me is the way the anti stall is able to give just the right amount of revs to get the car moving whereas my right foot on the gas pedal can’t. I would be very interested to learn how it works.The beauty of this is not only is it very compact (6 1/4" in diameter) allowing the engine to be located lower in the car than a traditional clutch getting the mass lower in the chassis, but it is extremely light meaning the engine revs with seemingly little inertia due to the lower rotational mass compared to a conventional clutch - 10 times less.
Used correctly they are very durable, and it's worth overcoming the aggravation of become conversant (I saw it as a challenge to master, rather than a problem) with it for the benefits offered.
Edited by 993rsr on Monday 15th April 18:38
I’m not sure it’s that sophisticated I’ve got a complete CGT workshop manual on an old pc so will take a look at some point if that gives any leads.
stefan1 said:
993rsr said:
Fabulous!
Interesting on the re-design of the differential parts, mine is due it's fourth 4 year engine out service next year and second has become notchy again, I had 3rd gear synchro replaced and one of the selector mechanism parts (which is now a paperweight in my office) by Hor a few years ago and will ask Reading to send the box back when the engines out.
I also had those selector parts replaced too...worth asking about the differential for sure.Interesting on the re-design of the differential parts, mine is due it's fourth 4 year engine out service next year and second has become notchy again, I had 3rd gear synchro replaced and one of the selector mechanism parts (which is now a paperweight in my office) by Hor a few years ago and will ask Reading to send the box back when the engines out.
Cheers
I’ll follow your lead on a return visit for the gearbox to Hor for a check over and the forged differential parts.
Turn7 said:
OOI, any idea on clutch replacement cost ? and expected life span ?
As others have said, a lot is made about the CGT’s carbon ceramic clutch, but the reality is that it’s a tough unit if used correctly.As to cost, the replacement part cost for the PCCC is £6118.12 plus vat + labour. There are other associated parts such as the release module and rear main oil seal that you’d probably have replaced at the same time. All-in for the PCCC and associated parts, your looking at £9,320.87 plus vat + labour. Factor in that you may never have to replace this unit, unless you muller it, then it’s something that you factor into your overall ownership.
Another observation is that I reckon the second clutch pack is noticeably easier to modulate than the first generation PCCC. I’ve heard from others that there was a slight redesign undertaken.
Anyways, went out for a drive this evening and there really is no other experience like it.
LaurasOtherHalf said:
Always wondered with the carbon clutch, do you just use it like any modern clutch nowadays?
As in, every modern manual car has anti-stall seemingly programmed in and I pretty much always use no throttle when starting off these days.
In a word no.As in, every modern manual car has anti-stall seemingly programmed in and I pretty much always use no throttle when starting off these days.
Plenty of explanations in the preceding posts
993rsr said:
LaurasOtherHalf said:
Always wondered with the carbon clutch, do you just use it like any modern clutch nowadays?
As in, every modern manual car has anti-stall seemingly programmed in and I pretty much always use no throttle when starting off these days.
In a word no.As in, every modern manual car has anti-stall seemingly programmed in and I pretty much always use no throttle when starting off these days.
Plenty of explanations in the preceding posts
LaurasOtherHalf said:
Care to explain more? Because it sounds exactly like how modern ECUs modulate throttle position depending on load from the other explanations and what I've read.
One difference is that if you even just so much as hint at using the throttle, the anti stall switches off and the engine promptly stalls.. The only other option, which I have never tried I hasten to add, is to use a bootfull of revs and hurtle up the road in a cloud of tyre smoke. According to Hunter and Yellow, 993rsr may be more familiar with this technique. (allegedly)
In all other situations (as in, apart from moving from a standstill) what’s the accepted technique then?
Be as quick as possible with it? Presumably rev match as much as possible so there’s as little slipping as possible?
As another poster said above, the fact it means you’ve got to learn to drive it slightly differently is all part of the appeal.
The drive train on these things is up there with the F1 really I guess.
Be as quick as possible with it? Presumably rev match as much as possible so there’s as little slipping as possible?
As another poster said above, the fact it means you’ve got to learn to drive it slightly differently is all part of the appeal.
The drive train on these things is up there with the F1 really I guess.
lowndes said:
LaurasOtherHalf said:
Care to explain more? Because it sounds exactly like how modern ECUs modulate throttle position depending on load from the other explanations and what I've read.
One difference is that if you even just so much as hint at using the throttle, the anti stall switches off and the engine promptly stalls.. The only other option, which I have never tried I hasten to add, is to use a bootfull of revs and hurtle up the road in a cloud of tyre smoke. According to Hunter and Yellow, 993rsr may be more familiar with this technique. (allegedly)
LaurasOtherHalf said:
In all other situations (as in, apart from moving from a standstill) what’s the accepted technique then?
Be as quick as possible with it? Presumably rev match as much as possible so there’s as little slipping as possible?
As another poster said above, the fact it means you’ve got to learn to drive it slightly differently is all part of the appeal.
The drive train on these things is up there with the F1 really I guess.
The F1 has a true carbon clutch which is a bit different from the carbon ceramic one in the cgt I think. As I understand things the carbon clutch (as used in the occasional race car as I've never got even close to being inside a F1) is considerably more grabby. The cgt clutch essentially is like a normal one but much lighter. The difference vs a more conventional modern car is that the cgt will stall much more easily if you slip the clutch too quickly (and as lowndes says you really don't want to even get close to the throttle to try to raise the revs). Be as quick as possible with it? Presumably rev match as much as possible so there’s as little slipping as possible?
As another poster said above, the fact it means you’ve got to learn to drive it slightly differently is all part of the appeal.
The drive train on these things is up there with the F1 really I guess.
In other use, it's just the speed of revs that is the issue. It's the only car I have to remind myself to be quick on an upshift as the engine revs much more freely (up and down) compared to say the 7.2rs which is supposed to have a lightweight flywheel.
isaldiri said:
LaurasOtherHalf said:
In all other situations (as in, apart from moving from a standstill) what’s the accepted technique then?
Be as quick as possible with it? Presumably rev match as much as possible so there’s as little slipping as possible?
As another poster said above, the fact it means you’ve got to learn to drive it slightly differently is all part of the appeal.
The drive train on these things is up there with the F1 really I guess.
The F1 has a true carbon clutch which is a bit different from the carbon ceramic one in the cgt I think. As I understand things the carbon clutch (as used in the occasional race car as I've never got even close to being inside a F1) is considerably more grabby. The cgt clutch essentially is like a normal one but much lighter. The difference vs a more conventional modern car is that the cgt will stall much more easily if you slip the clutch too quickly (and as lowndes says you really don't want to even get close to the throttle to try to raise the revs). Be as quick as possible with it? Presumably rev match as much as possible so there’s as little slipping as possible?
As another poster said above, the fact it means you’ve got to learn to drive it slightly differently is all part of the appeal.
The drive train on these things is up there with the F1 really I guess.
In other use, it's just the speed of revs that is the issue. It's the only car I have to remind myself to be quick on an upshift as the engine revs much more freely (up and down) compared to say the 7.2rs which is supposed to have a lightweight flywheel.
Taffy stick to a automatic mate
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