PCCB Conversion Question
03-07-2006, 06:22 PM
#16
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Originally Posted by viperbob
Hmm, some good ideas. I'll get a 997 GT3 rear rotor coming from Porsche Motorsports (again the same theory would hold that the Cupcar rotor will be less than 1/2 of the street car cost). I'll check first hand if it is a replacement option.
Go Bob! Please let us know what you find out.
03-07-2006, 08:05 PM
#17
Three Wheelin'
Originally Posted by Bob Rouleau
BobbyC - I cannot say. No experience with Gen II PCCB but I can't imagine that the Pagids would work any differently. The RS 29 pad is similar to the 19 with slightly more initial bite. I had some and observed that they are thinner than the RS-19s - perhaps this was a production tolerance thing.. I don't know. They were about 2 mm thinner - this could be an advantage though. When fitting new RS-19 pads to new rotors it is almost impossible to get them to drop into the caliper. based on what I saw of the 29s this would not be a problem.
With respect to the GT3 rotors, I prefer them. I buy replacements from Gert Carnewal in Belgium, he supplies the Motorsports version and landed in Canada they cost $400 Canadian dollars.
Several of my pals have gone to the floating caliper slotted rotors mentioned in this thread. The results have been less than stellar. The clacking noise is annoying and I would not put up with it. The hats wear (bolt holes get enlarged for some reason) so the idea of replacing rotors only is not as good an option as it might sound. You lose the hand brake since the rear hats do not incorporate the drum brake found on the GT2/GT3 hats. Lastly both guys who fitted them to their GT3 are complaining about a mushy pedal. I don't know why. I am sticking with the Motorsports rotors from Porsche.
Best,
With respect to the GT3 rotors, I prefer them. I buy replacements from Gert Carnewal in Belgium, he supplies the Motorsports version and landed in Canada they cost $400 Canadian dollars.
Several of my pals have gone to the floating caliper slotted rotors mentioned in this thread. The results have been less than stellar. The clacking noise is annoying and I would not put up with it. The hats wear (bolt holes get enlarged for some reason) so the idea of replacing rotors only is not as good an option as it might sound. You lose the hand brake since the rear hats do not incorporate the drum brake found on the GT2/GT3 hats. Lastly both guys who fitted them to their GT3 are complaining about a mushy pedal. I don't know why. I am sticking with the Motorsports rotors from Porsche.
Best,
Bob,
Alcon have fabricated a rear rotor that fits straight onto the ceramic brakes original hat for the rear (although they may have in fact made the hat too going by the price). This obviously preserves the parking/hand brake. Apparently alcon have reduced the float a lot on the fronts as well, so that they don't rattle, but I admit it is a concern for me and puts me off a bit. The guys I know who have them tend to not use their RSs on the road so don't mind the noise. Longetivity is apparently much improved though and I've not heard of feel problems etc. Specifically which disks are your friends using?
Frankly I'd be happy with a version of the OEM disks that were grooved rather than drilled as they'd hold up just fine for my needs without the potential noise compromises. Its the drill holes that cause all the hassle.
I think you may have had an odd batch of RS29s. Didn't someone post that they accidently made a batch which left room for the pad sensors. They are now of sufficient thickness to prevent that, or indeed the application of antisqueel shims until they are worn.
Anyway, I'm really hoping the 997 disk fits the rear because the alcon option is disproportionately expensive due to the tiny production volumes.
03-07-2006, 10:13 PM
#19
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Danh - the conversions are AP Racing I believe. They use slotted rotors and the claim is that the rotors are cheaper to replace than the Porsche Motorsports units. Being slotted, they are expected to last longer too. Mike K has them and he frequents these forums - perhaps he'll explain the problem he has with pedal feel.
As the the "thin" RS 29's you may be right. I had two sets of RS 19's which came with vibration dampers. Makes you wonder about their quality control.
Rgds,
As the the "thin" RS 29's you may be right. I had two sets of RS 19's which came with vibration dampers. Makes you wonder about their quality control.
Rgds,
03-08-2006, 11:13 AM
#20
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911 siverback, here's the answer to your question re the lawsuit>
I could not interest any lawyer in taking on the cases. None of them were interested in acting for an hourly charge, and thought the cases weren't potentially rich enough to support a contingent fee arrangement since, they thought, their chances of obtaining a jury award for punative damages were poor, due to the supposed affluence of the plaintiffs. Then, to compound the difficulty, several potential plaintiffs dropped out, once they learned that it was going to cost them money to prosecute the action. In the end, I had about eight plaintiffs left. I figured at least two of those would opt out when it was time to write a cheque, so I gave up my search for a lawyer. It ended with a whimper, not a bang.
Richard Bain.
I could not interest any lawyer in taking on the cases. None of them were interested in acting for an hourly charge, and thought the cases weren't potentially rich enough to support a contingent fee arrangement since, they thought, their chances of obtaining a jury award for punative damages were poor, due to the supposed affluence of the plaintiffs. Then, to compound the difficulty, several potential plaintiffs dropped out, once they learned that it was going to cost them money to prosecute the action. In the end, I had about eight plaintiffs left. I figured at least two of those would opt out when it was time to write a cheque, so I gave up my search for a lawyer. It ended with a whimper, not a bang.
Richard Bain.
Last edited by guykoken; 03-09-2006 at 10:57 AM.
03-08-2006, 02:01 PM
#21
Former Vendor
Originally Posted by viperbob
Hmm, some good ideas. I'll get a 997 GT3 rear rotor coming from Porsche Motorsports (again the same theory would hold that the Cupcar rotor will be less than 1/2 of the street car cost). I'll check first hand if it is a replacement option.
03-08-2006, 03:33 PM
#22
Nordschleife Master
guykoken: There is a perfect solution. Call Devek or go through a local shop that does business with Wrigthwood racing. They make great rotors. Here is how it works:
1: Fronts floating or not 350 or 360 mm irons(slotted) with R-19s
2: Rears they provide the rotor surface - you then use the original rear hts thereby maintaining the e brake and offsets.
They use great steel and have many ALMS and Rolex customers. Writewood does not sell direct so you will need to go through a shop.
1: Fronts floating or not 350 or 360 mm irons(slotted) with R-19s
2: Rears they provide the rotor surface - you then use the original rear hts thereby maintaining the e brake and offsets.
They use great steel and have many ALMS and Rolex customers. Writewood does not sell direct so you will need to go through a shop.
03-08-2006, 03:38 PM
#23
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Even though the Motorsports rotors are not as thick as the street ones 1) they seem to hold less heat from having less material 2) they weigh slightly less (about 1 lb) and 3) they seem to be able to get as many track days out of them as the street rotors...
03-08-2006, 04:35 PM
#25
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Peter, VBob and Dan - I agree. The Motorsport rotors with RS 19's die of cracks long before they hit minimum thickness. VBob may wish to comment, but my theory is that the 996 cars do not have enough brake cooling. I think that's why I replace rotors far more frequently than on my 993.
Mike K has the Brembo floating brakes on his GT3 and his slotted rotors don't seem to last much longer than my Porsche ones. I really suspect inadequate cooling. The 997 seems to have a lot more air gong to the rotors and I figure Porsche recognized the problem. I wonder if the Cup car ducts help prolong rotor and pad life?
Rgds,
Mike K has the Brembo floating brakes on his GT3 and his slotted rotors don't seem to last much longer than my Porsche ones. I really suspect inadequate cooling. The 997 seems to have a lot more air gong to the rotors and I figure Porsche recognized the problem. I wonder if the Cup car ducts help prolong rotor and pad life?
Rgds,
03-08-2006, 04:49 PM
#26
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If we increase the ride height on the 996 GT3 by 2 inches front and rear, and drive the car at 993 speeds, the front brake rotors won't crack.
cooling has been improved on the 997 GT3 by opening two holes on the front spoiler lip (suggested here long ago). The prevention of underbody airflow (good for aero), also prevents cold air toward the front brakes (bad for brakes). The problem comes from cooling. Rear steel or PCCB rotors don't fail that often, front steel and PCCB crack more often.
Cargraphics has a nice cooling kit for the GT2/GT3, a must if you hit the track very often.
cooling has been improved on the 997 GT3 by opening two holes on the front spoiler lip (suggested here long ago). The prevention of underbody airflow (good for aero), also prevents cold air toward the front brakes (bad for brakes). The problem comes from cooling. Rear steel or PCCB rotors don't fail that often, front steel and PCCB crack more often.
Cargraphics has a nice cooling kit for the GT2/GT3, a must if you hit the track very often.
03-08-2006, 06:15 PM
#27
Nordschleife Master
NJ-GT: you are right, the cooling kits are important. Look at the cup cars, they bring air from the back of the radiator to the rotors. You want cooling air not cold air.
03-08-2006, 06:28 PM
#28
Three Wheelin'
Heard some debate on the cooling kits. I might look into that a bit more though.
I just want to find the cheapest quality steel for the rear rotors without downgrading caliper, and a non floating quality disk from the front. Anyone got prices on the devek ones? These parts all seem disproportionately expensive. The prices I've been quoted would normally include new callipers etc on other cars!
I just want to find the cheapest quality steel for the rear rotors without downgrading caliper, and a non floating quality disk from the front. Anyone got prices on the devek ones? These parts all seem disproportionately expensive. The prices I've been quoted would normally include new callipers etc on other cars!
03-08-2006, 06:49 PM
#29
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Cooling is an issue with the front brakes. I have found that just using the Cupcar ducts helps quite a bit (about 20% larger than the street ducts). I just got these in today. Just in time for a pic. It is two piece, so if you break the main part, you can just get the lower half and pop rivet it in. They are also harder plastic.
Last edited by viperbob; 05-21-2009 at 09:20 PM.
03-08-2006, 07:00 PM
#30
Nordschleife Master
There is also a hard plastic piece that diverts air to the top half of the rotor.
The part in Vipers pic works great. Tire will rub at full lock but not a big deal other then the new noise.
The part in Vipers pic works great. Tire will rub at full lock but not a big deal other then the new noise.