997 GT2 PCCB Failure (brakes melt)
#76
Nordschleife Master
I suggest taking one of your other cars to a future DE as well as the GT2. Track the other car. Work with the DE organizer for a variance at the end of the day or at dusk to test your GT2 for a short session. Leverage 2 way communication, video and knowledgeable spotters in known braking zones. If your rotors are glowing while off the brakes or under acceleration, it should be clear, a computer aid is activating. Since you are blowing through pads, rotors and calipers at such an astonishing rate, I might be oversimplifying, but it seems just a few laps at the track and proper support/help could starting a basis for your root cause analysis. I can't imagine how frustrating this situation must be for you and your new Porsche. Best of luck getting this sorted out.
#78
Rennlist Member
I suggest taking one of your other cars to a future DE as well as the GT2. Track the other car. Work with the DE organizer for a variance at the end of the day or at dusk to test your GT2 for a short session. Leverage 2 way communication, video and knowledgeable spotters in known braking zones. If your rotors are glowing while off the brakes or under acceleration, it should be clear, a computer aid is activating. Since you are blowing through pads, rotors and calipers at such an astonishing rate, I might be oversimplifying, but it seems just a few laps at the track and proper support/help could starting a basis for your root cause analysis. I can't imagine how frustrating this situation must be for you and your new Porsche. Best of luck getting this sorted out.
Nero,
If you want to try this, Hooked On Driving is running under the lights @ PBIR June 20th.
Peter
#79
Any updates on the problem?
I also have problems with the brake system on my 997tt with BREMBO GT brake kit (have fr and rear kits)
When i drive the car fast and aggressive on throttle,
I mean full throttle and depressing throttle, again and again... (without braking)
The brakes start to make noise and too much vibration, like if i was using the brakes.
I think this problem comes from the "Brake Pre-fill system" on the 997tt.
Did anyone have similar experience with Brembo GT brake kits?
Thanks
I also have problems with the brake system on my 997tt with BREMBO GT brake kit (have fr and rear kits)
When i drive the car fast and aggressive on throttle,
I mean full throttle and depressing throttle, again and again... (without braking)
The brakes start to make noise and too much vibration, like if i was using the brakes.
I think this problem comes from the "Brake Pre-fill system" on the 997tt.
Did anyone have similar experience with Brembo GT brake kits?
Thanks
#80
Poseur
Rennlist Member
Rennlist Member
I'm curious as to what other cars you have been driving on the track for the last 6 years. Any brake issues? (I'm sure you would have mentioned it).
One thing for certain, racers don't change how they drive THAT much. What's your experience with the other cars? Any others with exotic brakes, i.e., ceramics?
How many years do you have racing 911s? (Rear engined Porsches).
One thing for certain, racers don't change how they drive THAT much. What's your experience with the other cars? Any others with exotic brakes, i.e., ceramics?
How many years do you have racing 911s? (Rear engined Porsches).
#81
You need a re-designed brake cooling system which would include significant changes to and replacement of several components. At the end of the day, GT2 is a street car, albeit an excellent one, and the brake cooling system is not that of a race car.
P.S. As to the cost to do a proper job, not a race shop attempt, it would easily be in excess of $200,000 -- and that assumes, among many other things: (i) four newly designed, reasonably priced fabricated steel uprights, not far more expensive fabricated or cast titanium, forged MMC, etc., (ii) four newly designed billet machined, not forged, calipers and (iii) carbon fiber pieces of excellent (i.e., F1 like) but not show quality. Of this, perhaps $100,000 would not be re-occurring in the case of multiple complete cooling systems.
P.S. As to the cost to do a proper job, not a race shop attempt, it would easily be in excess of $200,000 -- and that assumes, among many other things: (i) four newly designed, reasonably priced fabricated steel uprights, not far more expensive fabricated or cast titanium, forged MMC, etc., (ii) four newly designed billet machined, not forged, calipers and (iii) carbon fiber pieces of excellent (i.e., F1 like) but not show quality. Of this, perhaps $100,000 would not be re-occurring in the case of multiple complete cooling systems.
Last edited by Robert Linton; 10-24-2009 at 10:20 PM.
#82
Rennlist Member
Not that it is of particular relevance, but I recall being rather surprised to see a 997 GT2 pull into the car park at the Nordschleife during a Porsche Sport Driving School with clouds of blue smoke coming off of the rear pads after only one lap.
The car was driven by one of the instructors; I asked another standing close by about this, he remarked that the rear bias+TC/SC was the culprit.
wish I'd taken pictures, would have made quite a promotional for the school!
The car was driven by one of the instructors; I asked another standing close by about this, he remarked that the rear bias+TC/SC was the culprit.
wish I'd taken pictures, would have made quite a promotional for the school!
#83
Three Wheelin'
So strange, never had any problems!
But I can say that if your not smooth when lapping you can have the computer going off all the time...causing it to overslow the car.
Smooth in fast out! It really changed my perception of that, I am allot quicker now because of this!
I can now make it slide without the computer coming on.
But I can say that if your not smooth when lapping you can have the computer going off all the time...causing it to overslow the car.
Smooth in fast out! It really changed my perception of that, I am allot quicker now because of this!
I can now make it slide without the computer coming on.
Last edited by Z06; 02-26-2010 at 07:30 PM.
#84
I do have the same problem with my 997 Turbo MkII Pdk. I melted 2 brake clippers, broke 2 discs and 4 brake pads in less than 90 minutes. Replaced the PCCB's by steel discs, but then everything was broken after 60 minutes. Never have had any problems with my previous Porsches. Reaction of Porsche: excessive use of the car!!!
#85
For the last 13 years, when pushing unmodified PAG/VAG cars round the Nordschleife, I have had to be very careful about not getting on the loud pedal too early otherwise the rear brakes are smoked (even on Audis), unless they have mechanical LSDs, and even then the TC is a bit silly. TC is better when its integrated into the dif.
Anybody who has deep pockets might benefit from talking to Guido Frensmeyer for his alternatives to PCCBs, much more stable and reliable rotors and lovely billet machined calipers.
R+C
(my initial reaction when first testing the 997Turbo was how underbraked the car was)
Anybody who has deep pockets might benefit from talking to Guido Frensmeyer for his alternatives to PCCBs, much more stable and reliable rotors and lovely billet machined calipers.
R+C
(my initial reaction when first testing the 997Turbo was how underbraked the car was)
#86
I do have the same problem with my 997 Turbo MkII Pdk. I melted 2 brake clippers, broke 2 discs and 4 brake pads in less than 90 minutes. Replaced the PCCB's by steel discs, but then everything was broken after 60 minutes. Never have had any problems with my previous Porsches. Reaction of Porsche: excessive use of the car!!!
Last edited by 997gt3north; 11-01-2011 at 09:45 AM.
#87
Addict
Rennlist Member
Rennlist Member
Since this is your 1st post, I'm going to guess, maybe incorrectly, that you had all the aids on (TC,SC, etc). If they were off, I'm going to guess, maybe incorrectly, that the car would have been very out of control without the aids. If you add up all the laps of the drivers on this board at 100s of racetracks around the world - there would probably be over 1 million. To cook the rotors and calipers of a modern 911 in 60 / 90 minutes is both easy to do and impossible to do. Impossibly if you are smooth and fast, easy if all aids are on and you are in a drift competition as you have 500hp and the TC/SC/ABS will be constantly on for 90 minutes. If you want to have fun and drift the car - turn off all the Aids - it is pretty simple.
#89
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the 997.1 GT3 has no CBC and when TC is turned off you are on your own.
the 997.1 GT2 has CBC as others have stated. I had no idea it would be so troublesome.
If you are pounding your car at the track i would suggest using the 997.1 CUP rotors which will fit in your 997.1 PCCB pots. Also try a Pagid RS29 pad or even the Porsche Motorsport pads.
This way you are not eating those expensive PCCB rotors.
You should also get the 997.2 rear brake duct upgrade to help cool down them rear brakes.
Anybody here know how to defeat CBC or have had similar problems in their GT2??
the 997.1 GT2 has CBC as others have stated. I had no idea it would be so troublesome.
If you are pounding your car at the track i would suggest using the 997.1 CUP rotors which will fit in your 997.1 PCCB pots. Also try a Pagid RS29 pad or even the Porsche Motorsport pads.
This way you are not eating those expensive PCCB rotors.
You should also get the 997.2 rear brake duct upgrade to help cool down them rear brakes.
Anybody here know how to defeat CBC or have had similar problems in their GT2??