Earlierapex

Thanks (I think ) Are these pads designed for ceramic rotors?

TrackDays247.com

They are 100% for PCCB brakes, really the only choice besides the stockers. People love em. In stock as well

PierreTT

OEM pads for me
They are very good on the track

s996

I now have about 4 track days in 3200 miles and to be honest the pads and rotors look almost like the first day I owned the car. I know it's still early in the life cycle of this car but the wear rate appears to be minimal. The pads have about 7 mm remaining thickness on the front and 8 on the rear.

We have a pretty good spattering of at least subjective data from about 4 days to what looks like 20 track days with only pad changes. When do you guys think the pads should be swapped? Thickness? Or only with electron resistance measurement?

When to swap to new rotors? change to steel?
I realize there is not an real answer to the questions but I am starting to think about all of the replacing and swapping and such that will come over the next year or so and would like to get your opinions

Karl911

Earlierapex,
I have worn out 2 sets of MSC2, and set of Dunlop race max.
Currently running a set MSC2 daily driver.
And running a set of Trofeo R for track.
Pads I have just been using OEs

alaint101

Salut Pierre (Garneau?)

I met one of the engineers from Brembo in Atlanta a few weeks ago. Too much info to put in a note here but here are some highlights.

1. I run the stock PCCB rotors and pads and after 12k miles and 6 hard track days, everything looks good
2. You cannot measure the new rotors on dimensions to assess wear - dealers use a tool to measure carbon density - because it won't change at all (long explanation)
3. They suspect it might last 'the life of the car' even if tracked hard - one example with 918 ran hard on track as demo over 12 months / 20k miles had only consumed 5% of the carbon in the rotors

You may want to talk to the folks in Atlanta and see if you can connect with the break folks. It was very interesting discussion with lots of technical stuff. Convinced me to reiterate w/ PCCB on the RS. (Should be in by end of month... )

jlanka

I'm liking this statement.

W8MM

This matches with info I received from David Donohue when he let me drive a demo 918 last Fall. I asked about PCCB durability of the 918 and he told me that the particular 918 we were driving had 7K miles on the odometer. 4K of those miles were track usage during which the brakes were "seriously abused". He later confirmed that the only brake maintenance was the changing of pads and that the factory folks saw no reason to change the PCCB rotors, ever.

TRAKCAR

Life time rotors is a pipe dream if you track 30-50 track days a year, half of them at Sebring.

My guess is you need to refurbish / replace all 4 corners every year. At least, if you replace pads often at 25-50% life of the pad.

ipse dixit

This may be true for Gen 2 PCCBs.

But the newer Gen 3 PCCBs have not been in use long enough to make any determinative statements.

If what Donohue and PAG are correct about the utilization rate of the PCCBs on the 918, then even 30-50 track days a year (which depending on where and how you drive may be 4k) may not disintegrate the Gen 3 rotors, as they would have with Gen 2 rotors.

It's probably too early to tell. But all early signs indicate that these new low fiber Gen3 rotors may hold up significantly longer than its predecessor.

Nodrip

It's supposed to be a facts topic, but since there is a lot of "talks", I will share what I heard from a Porsche salesman :
One of his client replaced his PCCB from his 991 GT3, after only 8000km...

Unfortunately, I have no more infos about it...

jlanka

coming from a salesman. Totally reliable.

GrantG

I don't know the answer to this question, but just thought I'd remind you that the 918 has regenerative braking with its hybrid system. So, much of the energy of braking is converted to electricity to recharge the electric power system's battery rather than heating up the rotors as in a conventional car.

TrackDays247.com

Carbon density - wow, that really does make sense! I suspect then that the internal content of the rotor would decrease over time more so and more meaningful than a thickness measurement.

Petevb

The PCCB rotor is a ceramic held together by carbon fibers. Think concrete with steel reinforcing or fiberglass with epoxy resin. Both the ceramic and the carbon fibers can withstand extreme temperatures, but carbon exposed to the air will oxidize (essentially burn) when it gets very hot. As it burns away it leaves the ceramic unsupported and with tiny voids, so thickness doesn't change. And because little carbon is lost visual and weight checks are inaccurate- hence the tool, and why we need more measurements from it rather than "the rotors look good". Looking forward to more measurements...

Like concrete without rebar the rotor loses integrity when the carbon is gone.

Oxidation is a highly non-linear process. It increases exponentially with temperature, so beyond a certain point even a little more temperature will increase wear dramatically. The critical variable is how hot the brakes get, and that varies with track and driver. Good drivers will often know if they are hard on brakes or not, but not going through pads quickly is a good indication you're not getting the brakes too hot.