Manifold

How much more pressure? In the car I'm buying, it's at least 50% more. I drove a 991.2 GT3 RS on track, and I don't recall which brakes it had, but the pedal felt the same as my 991.1 GT3. My wife drove the car, and the first time she hit the brakes, she was alarmed that the car wasn't slowing, even after she was forewarned.

Dguth

That does sound excessive and wonder what would be the cause if pads and rotors appear adequate. Wonder when the last time the fluid was replaced.

Derfe48

About noise and not braking properly :
- what kind of brake fluid
- Age of brake fluid
- Overheated brake fluid if not high temperature resistant can cause poor pedal feel
- What kind of pads (more agressive pads = less friction when cold)
- Overheated brake pads can cause uneven surfaces (holes) and when you brake it's like you have sand or very small rocks between discs and pads.
- Caliper piston issue ?

The car has been tracked so those issues can happen.

Or it can be normal brake deposit. I track my 991.2 GT3RS with PCCB quite often and when driving normally it's like I have sand between pads and discs but on track it's just fantastic.
I agree brakes can feel they are not working porperly when driving slow on my car too.

juanpablo046

I would be worried, you should take it to the dealer.
I'll ask the dealer to check brake pads (condition and brand/model) and rotors. If no issues there I'll ask them to change brake fluid and test again.

I've used PCCB in several 991.1 and 991.2 with nothing like you mention, including using the car after parking outside with under 0 degrees celcius and using the car after leaving it for hours with over 30 degrees celcius.

Manifold

Car is being sold by my dealer, and we will check everything carefully. They have the Carboteq tool to check the carbon content of the rotors; surface circular wear indicators don’t show wear (can’t see them). Will likely just replace the pads. That leaves fluid, master cylinder, and brake booster to be checked.

Hinz Motorsport

You may also try switching to the Pagid RSC1s if you are putting new pads on...good street manners (even when cold) and very low dust/noise. Super capable on the track as well when called upon.

Manifold

They work with CCBs?

Hinz Motorsport

Yes, specifically designed for carbon ceramic discs.

Manifold

I just learned that the pads were replaced last year, using pads supplied by the customer. This was in association with a track inspection, and the customer inquired about track alignment. Will find out soon enough, but I wonder if the pads aren't OEM pads. Are there track pads which work with the CCB which are good on track, but lack friction on the road?

juanpablo046

Could be, I had wrong pads installed once (low quality textar) on my 997.1 PCCB. The car just did not brake, needed much more effort to diminish speed even under 70 km/h, they didn't even last the day.

Derfe48

About RSC pads
RSC1 : slightly better than OEM, OK for track use but if you track hard you will overheat them and get holes at the surface.
RSC2 : not design to work with our kind of ceramic discs (there is 2 types of ceramic discs)
RSC3 : Better for track use, will handle more heat, has more friction, won't fall apart ;-)

I destroyed some RSC1, now I have RSC3 and so far happy with them.
Next pads are going to be RSL1

RSC3 and RSL1 will wear discs quicker.

Manifold

Why not just use the OEM pads?

Derfe48

If you track the car with OEM pads, and you break hard, you will destroy them quickly because they don't withstand heat too much.
After, the feeling is like you have sand between pad and disc. Not a good feeling at all.
And if you go back on track after this, it's not just a bad feeling, it's really annoying.
Plus they can fall apart because of this.

If you go on track occasionally and don't brake to hard they might be OK.

Manifold

Interesting, never heard this in the threads for tracking 991 and 992 TTS. Is there a thread for tracking 991 GT3/RS with PCCB?

Derfe48

You can find plenty of threads about track use with PCCB, it's a big subject.
There is a lot to know.

Some people swap to steel because they don't want to use their PCCB on track.
Some people track with PCCB but it's not really recommended.
Some people go for surface transforms ceramic discs like me.
I wanted to keep the weight benefits AND track my car a lot so ST is the way to go in my opinion.

Original PCCB don't withstand to much track use and they cost a fortune to replace.