FredtheFrog

Hello members,

I might have a dumb question but did somebody already experienced the mix with Front PCCB brakes and Steel on the rear?

You can imagine my car has the rear PCCB dead and i don't have the full budget for new ones (nor refurbished).

Your inputs are welcome and please don't threw me rude words!!
Thanx

FLT6SPD

Iron all around, never mix rotors, tires, ect.

Why do you thing your rear pccb is done?

FredtheFrog

They have a wear indicator, a small round of 8 mm on the braking track, which appears when disc is done. And they appear on each side.
Only 30000 km ... we are far away from the 300Kkm promised by Porsche!

RAudi Driver

Remove the fronts and sell them to fund your steel setup.

Colorado964turbo

Just because the indicator is there it doesn't mean they are end of life.

Can you get them weighed? Isn't that the best way to tell?

CRex

Don't mix. Different coefficients of friction altogether. It'll give your ABS hell.

Just go all irons like others have said.

FredtheFrog

Thanks for all the answers guys.
ABS/ESP is managed by the wheel speed sensors (+ yaw rate sensor+steering angle sensor) so until a lock from a wheel comes the system will manage anyway.
For sure the friction coef might be different, but this the same when you use different compounds of brake pads, no?

I think the PCCB is a great advantage in terms of unsprung masses and really impact the car behaviour and responsivness. I would really want to keep them at least on the front. Why the hell do they sell rotors that price??? Unbelievable.

About wear Indicators, when they appear it's time to change or rebuild.
Any advice on REBRAKE?

I saw a guy on YT (Jim Wong) who only change the rear for steel on a 997 Turbo. Rear ones seem to be more prompt to wear. But don't know if he is happy with the change or not.

bweSteve

Does anyone have the weight numbers (front & rear) for PCCB rotors, both for brand new, as well as when Porsche recommends they be replaced? Also not sure if .1 weights are different than .2 weights (brand new).

Since Porsche stamps the rotor max(new) & min thickness numbers directly on the inside of the PCCB,... I would have suspected that if max-min weights were relevant to the question on when to replace, ... those numbers would be published too.

rbahr

I would not depend on the electronics to sort out effect from mismatched parts. As others have said, use the same technology front and rear

Colorado964turbo

I thought the weights were on the hats as well.

Fred, you are incorrect on the wear indicators, do a search as this has been discussed a ton.

Steve Theodore

Unless you really do want to road race, don't worry too much about it. My 2010 GT3 RS has 'dead' rotors all around, meaning all show the wear circles...and have for about 7 years now. For street driving, it's not a problem whatsoever. For track driving, it is no longer considered safe. My PCCB rotors have 67k miles on them and still work splendidly on the street, and my car is on it's third set of brake pads with the original discs.

People do occasionally mix CCB fronts and iron rear discs, but I've only seen it done for straight line racing and on the R35 GT-R platform, not 911s. I agree that it's not wise to do, and do not recommend mixing them.

RAudi Driver

Three ways to measure PCCB's and all three should be implemented.

Here's a great video that explains it all. Also read in Porsche workshop manual that the circles are 2cm and if 50% surface degradation, then replacement is warranted. You should always be able to see the rings even on a new car if you look closely enough.


This machine from Snap On is almost $7,000

RAudi Driver

Old ad for new PCCB's. Look closely and you can see circles.

New PCCBs

Steve Theodore

That's interesting that you can see the wear circles when they are new...I didn't know that tidbit at all.

RAudi Driver