Dual Brake Masters/floor pedals.
01-17-2019, 09:05 AM
#31
RE GT3 (997 generation):
Front for 997.1 NON PCCB 6 piston: 28, 32, 38mm
Front 997.1 PCCB, 997.2 all 6 piston: 28, 30, 32mm
Rear All: 4 piston 34mm
The master cylinder is the same across all 997.1 and 997.2.
The 997.1 non PCCB cars use a smaller front rotor. The Fronts on all others are the same size 380mm
Front for 997.1 NON PCCB 6 piston: 28, 32, 38mm
Front 997.1 PCCB, 997.2 all 6 piston: 28, 30, 32mm
Rear All: 4 piston 34mm
The master cylinder is the same across all 997.1 and 997.2.
The 997.1 non PCCB cars use a smaller front rotor. The Fronts on all others are the same size 380mm
For some reason Porsche has chosen to be very close mouthed about a lot of the specs on these cars, I've needed to resort to IMSA spec sheets for a lot of tech on the 996 and 997, more for aero & such, the mechanical tech is mostly available on the PMS side
01-17-2019, 01:36 PM
#32
Rennlist Member
After taking a deep dive into the parts books it appears that the 996GT3 used the 28/30 rears up though at least 2005, I haven't looked at the 2006 docs but 997 gen 1 from 2007 used the 34/34 rears, bias w/ these is 1.608, this is something I had missed. I still like the 997RSR 28/36 rears much better.
For some reason Porsche has chosen to be very close mouthed about a lot of the specs on these cars, I've needed to resort to IMSA spec sheets for a lot of tech on the 996 and 997, more for aero & such, the mechanical tech is mostly available on the PMS side
For some reason Porsche has chosen to be very close mouthed about a lot of the specs on these cars, I've needed to resort to IMSA spec sheets for a lot of tech on the 996 and 997, more for aero & such, the mechanical tech is mostly available on the PMS side
See if you can track down the motorsport catalogs. They list all the parts.
I only know this from having tracked a 997.1RS for over 6 years and many of the bits come from cup cars or can be swapped in.
I will say this though: the braking on the 997 cars are fantastic. The ONLY real gap in my mind with proper rotors and pads is the ABS system. Its a street system and YES there is ice mode. Usually hit on bumpy braking zones at threshold levels. You learn to work around it, and you need to because if you don't, you will wreck your car. First time I got it went off in a corner just in the dirt. Freaked me out. Then, I went to tackle the issue, practicing hitting it (lower speeds) and learning to react (get out and back into the pedal FAST), and not inducing it (ie braking off line). Learn your tools right? :-)
01-17-2019, 01:44 PM
#33
The front/rear brakes for the 997.1/2 CUP are the same as the .1PCCB/.2 cars, they used a different rotor with a floating design, and different hole pattern that can direct swap to the street cars. Still not a great rotor really. I use brembo full floating type5 f type 3r. But I believe the cup used a dual tilton master with a bias adjustment. No ABS either, the 996 cup had ABS. Most guys will add the Bosch M4 ABS to the car as well, 3-4 flat spotted sets of tires and you've paid for that thing. The R/RSR are a different brake package. They tended to use a race caliper from brembo that took endurance pads. For the 991 generation they switch to a totally different brake package than the street cars. 997 generation was quite close to the street cars. I have a few caliper rebuild kits on the shelf with pistons/seals and they are motorsport parts.
See if you can track down the motorsport catalogs. They list all the parts.
I only know this from having tracked a 997.1RS for over 6 years and many of the bits come from cup cars or can be swapped in.
I will say this though: the braking on the 997 cars are fantastic. The ONLY real gap in my mind with proper rotors and pads is the ABS system. Its a street system and YES there is ice mode. Usually hit on bumpy braking zones at threshold levels. You learn to work around it, and you need to because if you don't, you will wreck your car. First time I got it went off in a corner just in the dirt. Freaked me out. Then, I went to tackle the issue, practicing hitting it (lower speeds) and learning to react (get out and back into the pedal FAST), and not inducing it (ie braking off line). Learn your tools right? :-)
See if you can track down the motorsport catalogs. They list all the parts.
I only know this from having tracked a 997.1RS for over 6 years and many of the bits come from cup cars or can be swapped in.
I will say this though: the braking on the 997 cars are fantastic. The ONLY real gap in my mind with proper rotors and pads is the ABS system. Its a street system and YES there is ice mode. Usually hit on bumpy braking zones at threshold levels. You learn to work around it, and you need to because if you don't, you will wreck your car. First time I got it went off in a corner just in the dirt. Freaked me out. Then, I went to tackle the issue, practicing hitting it (lower speeds) and learning to react (get out and back into the pedal FAST), and not inducing it (ie braking off line). Learn your tools right? :-)
yes, ICE mode has been a big problem w/ the street ABS usd in Cayman and GT3, A friend bought a new 997 Gen2 GT3RS He got the factory to replace all the calipers and the ABS components under warranty and finally threw up his hands in disgust and put a $10k PFC system on the car, sold it and bought a 964Cup, said he was never happier
01-17-2019, 01:57 PM
#34
Rennlist Member
I've got all the Motorsports catalogs from ~1995 covering every version Cup and RSR
yes, ICE mode has been a big problem w/ the street ABS usd in Cayman and GT3, A friend bought a new 997 Gen2 GT3RS He got the factory to replace all the calipers and the ABS components under warranty and finally threw up his hands in disgust and put a $10k PFC system on the car, sold it and bought a 964Cup, said he was never happier
yes, ICE mode has been a big problem w/ the street ABS usd in Cayman and GT3, A friend bought a new 997 Gen2 GT3RS He got the factory to replace all the calipers and the ABS components under warranty and finally threw up his hands in disgust and put a $10k PFC system on the car, sold it and bought a 964Cup, said he was never happier
Anyway, I'd love a 964 cup by my little hot rod is probably not terribly far off...
01-18-2019, 08:05 AM
#36
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Master Cylinders
Looking at the pictures of the 993TT, 996, 997 and Cayman that you posted has me wondering if the change to the Cayman MC would be the easiest move. Looking at the mount ends of each they appear to be very similar. The questions that need to be answered are - 1. What is the outside diameter of the portion of the MC that fits into the booster housing and 2.what is the length of the operational push rod. If these match up or are close to the stock 993 (23.8) MC then the change to the Cayman (25.8) could work with little modification. So all this leads to the question - Does any one know what these sizes are? Does anyone have these 2 MCs around to check sizes and length. Or does someone have/know the measurements. Certainly would help determine my next steps.
01-18-2019, 10:04 AM
#37
Looking at the pictures of the 993TT, 996, 997 and Cayman that you posted has me wondering if the change to the Cayman MC would be the easiest move. Looking at the mount ends of each they appear to be very similar. The questions that need to be answered are - 1. What is the outside diameter of the portion of the MC that fits into the booster housing and 2.what is the length of the operational push rod. If these match up or are close to the stock 993 (23.8) MC then the change to the Cayman (25.8) could work with little modification. So all this leads to the question - Does any one know what these sizes are? Does anyone have these 2 MCs around to check sizes and length. Or does someone have/know the measurements. Certainly would help determine my next steps.
01-19-2019, 05:11 PM
#39
02-01-2019, 11:10 PM
#41
Just to bring a little more info here regarding master/caliper sizing. Race Technologies was pretty adamant that their engineers had the balance right for the given masters on each chassis. I then pointed out that for 964’s with 993 carriers they are selling front sets calculated for the 993 master paired with rear sets calculated for the smaller 964 master which would then increase the bias to the front more than their own engineers would specify for the 964. I mentioned that 993 rear calipers with the 964 disk would make a balanced bolt on set.
The sales person I am working with for what ever reason did not or could not produce the caliper bore info on the sets I’m interested in. (However I did get the weights) In the end I’ve supplied the front reat weights, tire info, abs, master etcetc. and he is passing that on to the engineers- they will calculate based on that info. He made it clear that they will not spec a system based on use preference. I can not request a particular bias. It will be interesting to see what they come up with.
They offer this service for dedicated track cars so anyone looking at replacing all calipers on their track cat this might be a good way to go.
Pete
The sales person I am working with for what ever reason did not or could not produce the caliper bore info on the sets I’m interested in. (However I did get the weights) In the end I’ve supplied the front reat weights, tire info, abs, master etcetc. and he is passing that on to the engineers- they will calculate based on that info. He made it clear that they will not spec a system based on use preference. I can not request a particular bias. It will be interesting to see what they come up with.
They offer this service for dedicated track cars so anyone looking at replacing all calipers on their track cat this might be a good way to go.
Pete
