carrering

i have a great 07 GT3 with steel brakes which is my first porsche. loved the braking feel from day one. I do not enjoy changing rotors so frequently however. i have an opportunity to order a 10 RS and after debating this option for the last 6 months. I was set on getting them but then i searched "pccb" on the forum and found the scary issues with green fade. Is this just a pccb and pad choice issue? will getting the motorsport green pads prevent this and will they not eat up the expensive rotors?

I know if i swing through the pit and the steels cool down a bit the braking is a bit dicey on the first lap back out. is this a similar issue with the pccb's or magnified b/c they cool off so much faster?

sws1

Green fade happens once. Then it's over. Scary. But if you know it's coming your first time out on the track, you can prepare for it.

sws1

Oh and certainly nothing that would prevent me from buying PCCBs if I wanted them otherwise.

997gt3north

Green fade is a pad issue with new non tracked OE pccb pads - ie almost impossible on street driving to get them up to temp to get the gas release - the 10 stops from 100 to 5 prior to the pads first event is a 99% succesful solution

With OE pads you are not exactly good to go 100% on the first corner (they will work for sure) but they need a few corners to give you 100% braking (lets say 85% for first 3 corners then 100%)

With the P50 (Green Pad), the 1st corner is maybe 40%, 2nd corner maybe 60%, 3rd corner 80%, 4th 85%, 5th 90%, 6th 95% then 100% (this is my guestimate based on using 4 sets of Greens)

The biggest differences are:
- first 2 corners on Greens you have substantially less braking power than with the OE pads
- they cool down much faster (drive through the pit and you must warm them up again)
- there is slighly higher friction with the Greens than the OE pad once warm (not dramatic but noticeable for sure)
- the Green Pads "feel" harder (you have to drive both to understand)

The other PCCB issue you will go through is the initial on/off "feel" & a high bite point that will change once you truly light them up on the track for the 1st time. You have to be ready for this. When you first take delivery of the car you will be blown away with the difference in "initial" feel between Irons and ceramics. When you touch the brake pedal when new with ceramics, the bite point is very high and the car stops immediately - your brain then says "wow, these are unbelievable", and they are except that type of on/off action would be impossible to use properly on the track (on/off + high pedal = very difficult heal/toe). I have concluded after much research that the ceramics rotors when new have a friction surface that needs scrubbing in and until this happens it is the friction of the rotor againnst the pad that causes the slowing and not the thermal properties of the pad and the rotor - this can only happen when your truely light them up and scrape / sand down that most outer layer of the rotor - when that happens, I warn you, you will think the fluid has boiled, your brake pedal will drop approximately 1 inch and will now perfectly line up with the throttle for heal toe and (and this is the important part) the pedal feel will change dramatically forever from on/off to what "feels" like mushy (but it is not it is just no longer on/off) - now the brakes can be easily modulated - i.e. they are worked in.

In terms of ceramics vs. Irons
- ceramics are better but cost more - that's it in a nutshell
- ceramics with Green P50s will give you that Irons with Race pad feel (better initial bite) but will still feel even better and cannot be faded
- with Green Pads you should get 50 to 80 trackdays from the rotors (this is my estimate)
- disable TC and SC so you don't unknowingly abuse the rear rotors

Paul

Greygt3

What Paul said. I've had two GT3's with PCCB that get tracked regularly and I highly recommend them.

russo

So far no complaints on the PCCBs.

carrering

thanks for the inputs and warnings.

i came across this article on bedding pccb's in. would this also be the case for bedding in new green pads?

http://www.total911.com/news/how-to-...eramic-brakes/

seefouress

[
The other PCCB issue you will go through is the initial on/off "feel" & a high bite point that will change once you truly light them up on the track for the 1st time. You have to be ready for this. When you first take delivery of the car you will be blown away with the difference in "initial" feel between Irons and ceramics. When you touch the brake pedal when new with ceramics, the bite point is very high and the car stops immediately - your brain then says "wow, these are unbelievable", and they are except that type of on/off action would be impossible to use properly on the track (on/off + high pedal = very difficult heal/toe). I have concluded after much research that the ceramics rotors when new have a friction surface that needs scrubbing in and until this happens it is the friction of the rotor againnst the pad that causes the slowing and not the thermal properties of the pad and the rotor - this can only happen when your truely light them up and scrape / sand down that most outer layer of the rotor - when that happens, I warn you, you will think the fluid has boiled, your brake pedal will drop approximately 1 inch and will now perfectly line up with the throttle for heal toe and (and this is the important part) the pedal feel will change dramatically forever from on/off to what "feels" like mushy (but it is not it is just no longer on/off) - now the brakes can be easily modulated - i.e. they are worked in.

Paul[/QUOTE]

Awsome feedback Paul. I like the PCCBs a lot but have not tracked my RS yet and they still have that "on-off" feel. I had not read about the changes (in both feel and pedal position) that takes place after lighting them up and look forward to experiencing that. Thanks!

sws1

I disagree with the comment that the bite doesn't come back. If you don't track your car for several months, the pedal feel does come back from that mushy feeling to the feeling you had when the car was new.

Each time I tracked the car, I left the track feeling like I had to give alot of pedal to make it stop, with a much lower pedal. After a few months, the pedal and bite slowly came back. In my head, I had assumed I had glazed the pads at the track, and they took lots of street driving to remove that glaze.

carrering

do the owners of pccb equipped '10 gt3s notice the same "feature" as the MK1's?

Nizer

Proper bedding procedure yes, but probably best reserved for the track. I doubt the locals authorities would take too kindly to the explanation that you were doing repeated deceleration runs from 100+ to 50 on the street in order to bed in your ceramic brakes....

Bob Rouleau

FWIW if you search a lot you will find a number of people with PCCB equipped GT3 and GT3 RS who are switching back to conventional rotors. These are people who track frequently.

My 2010 RS will NOT have PCCB. The reasons are:

1) Braking performance with steel rotors and Pagid RS 29 pads is outstanding and as good as any PCCB set up.

2) Pads for steel (iron really) rotors are much cheaper than the PCCB pads available exclusively from Porsche. There is also a far better variety.

3) The new iron rotors are not that much heavier than the latest PCCB.

4) The option price of PCCB rotors will pay for conventional replacement rotors for a lifetime!

5) If like some, you are required to replace a PCCB rotor the price is eye watering! Ask your parts manager how much he wants for a pair!

6) Cup cars and the RSR use conventional rotors and nobody complains about brake performance on those cars. The 2010 RS
uses the same brakes as the race car. Good enough for me!

7) Nobody with conventional brakes complains about Green Fade and difficulty with heel and toe caused by a brake pedal which is too high.

Lastly this is based on my perspective. I track my car at least 50 days per year and my rotors last a season. At about 400 bucks each I spend more than that on pads in any given season and far more on tires


Best,

carrering

i live in germany. probably not a problem.

carrering

all great points especially on the cost. what type of rotors are you running on your current RS? I'm amazed you can get 50 track days out of a set of rotors. oems cracked at 7k miles with moderate track use and by 8k were toast. replaced with PFC floating rotors up front and new oem in back. the first set of PFC's seem to be holding up pretty well but it looks like they would only last about as long as oem's.

Bob Rouleau

Fronts are DeMan slotted. Rears are OEM. I never use traction control which uses up rear rotors very quickly. Use 997 GT2 rear brake cooling ducts. Pagid RS 29 pads all around. Proper braking technique helps as does proper bedding of pads. I use Motul RB 660 fluid changed every 6 months.

Best,