WP0

Having just switched to iron rotors fom PCCB in the same car, driving on the same track, I speak from experience when I say:
I agree that the wheels stay cleaner with PCCB. PCCB does save weight (but I can't appreciate any better performance as a consequence). Most importantly, PCCB stays cooler on the track, thus keeping tire pressures more stable; however, the iron/steel rotors have a better feel, and don't need to warm up like the PCCB do. (PCCB are always downright scary the first few brake applications.)

job511

Sorry to hi-jack the thread..... I am also learning these PCCB breaks on a vehicle. In terms of rotors and pads, what am I looking at when it looks worn or beat up?

** I know the 2nd set of photos showed PCCB are in better shape. I just don't know what I am looking for or looking at ? Can someone point that out?

many thanks

WP0

I think this sums it up rather well:
From my post above:
Otherwise, you can look for cracks between drill holes, chips (I think I see one in the last photo), irregularities on the surface, and feel for roughness (they should be smooth to touch).
Superficially, they look OK to pass a CPO, but I would get the rotor thickness measured by the laser device at a dealer.

Psup4s

I agree with the weight savings and less/no dust on wheels. However if wheels are coated cleaning them is nots as difficult. As far as "feel" goes I have no idea and frankly dont remember feeling any difference than steel.
Do pccb have better braking power? if they significantly do I can see the appeal in getting them but I'm not so sure they do.

I think this may be true and the fact that this thread was created adds to my belief that pccbs in used cars (specially GT3/RS) may not be worth it.

Alan C.

Same experience. Would NOT spec PCCB.

Psup4s

Thanks for confirming this

mdrums

Original photos looks like the brakes were washed....good thing to do by the way...and left to dry and car wasn't moved. My PCCB will look like this too then I drive down the street and they look clean again. They can look like this too after a track day but clean up over a few days or so of street driving.

Pads at 2mm pad material on PCCB is not a good thing. PCCB pads need to be changed out at 50% thickness and that is around 7mm...plus flipping pads side to side after 2-3 track days is a good idea too to keep pucks from cracking.

Only way to measure life of PCCB rotors is the scan tool at a Porsche Dealer.

WP0

Mike, How does flipping pads from side to side prevent puck cracking? (By side to side, I assume you mean from inside right front rotor to outside right front rotor, and not from right front rotor to left front rotor.). Do you do flip the pads yourself, or take it to the dealer? If you do it yourself, what size tools are needed for your PCCBS on your GT3 (e.g. size 20 torx, etc)? Thanks!

mdrums

Flipping the pads keeps the wear straight from inside to outside of the pads.....thus when the brakes are applied and the pistons/ceramic pucks push the pads to the rotor they are pushed with a even force and not angled. Then the pads wear they do not wear evenly and the angle the pucks are pushing on the pads will cause the edge of the pucks to crack.

I flip pads my self. You will need new caliper bolts as those need to be replaced each time....torque is 63ft lbs..... 8mm Hex

FORENN

+1

Agent_Orange

Oh yes, PCCBs definitely have that stronger bite meaning later braking points

CAlexio

They don't have better braking, except some studies show that over REPEAT braking they are more consistent. What I meant by "better feel" has to do with the brake booster calibration... pccb brakes feel firmer at the pedal, but previous knowledge on threads had concluded this is just a calibration? They definitely have a firmer pedal which I love on track.

Next car I'm still going steel brakes then will spend the $ on the aftermarket refurbishable options as durability of pccb on track remains a massive question mark for me.. UNLESS, Porsche introduces something truly new and track proven on 992 GT3.. will wait and see I guess.

Psup4s

Thank you for clarifying. It would be great if same brake booster calibration could be applied to steel brakes if both systems use same booster.
I agree with you on the durability of pccb on track and for now prefer the steel brakes as the benefits still don't outweigh the price point imho.

JRitt@essex

To the OP, if you do end up buying the car, put the PCCB's on the garage shelf so you don't have to go through this with the next buyer! Our AP Racing iron system offers nearly the same weight savings as the PCCB discs, but with a laundry list of other added benefits:
https://rennlist.com/forums/991-gt3-...t-finally.html

CAlexio

Question.. can your RADIcal calipers be mated to the refurbishable composite disks advertised by other vendors on Rennlist for even greater weight savings? Or even the stock pccb? It would seem that saving weight at both the caliper AND the rotor would be the bi-winning solution no?