Brake cooling

[bman]

Great info Peter, thanks!

I've been following your threads on rotors, pads and cooling anticipating the need to upgade my components. But I've had an "unusual" experience with my car.

I switched from PCCB's this past March. I replaced with a lightly used set of '10 Cup rotors and calipers. The rotors are the same as the stock .2 GT3 steel. The front rotors had a moderate amount of cracking but nothing near the edge or interconnecting between holes. Assuming they wouldn't last long I purchased a backup pair of front rotors at the same time. Surprisingly I have not changed the original USED rotors and have about 18-20 days on them. Cracking has grown but still not at the point where I would replace. Granted I don't have the harsh Florida heat but I have run many days with ambient temps above 95f.

I am baffled by this......I fully expected to have replaced the original rotors and the replacement set by now. I don't know if it's a fluke, something to do with the GT2 cooling or the CUP caliper. Hopefully someone will come to my defense when it comes to driving hard....... I have stopped late braking every corner, not sure that makes a difference.

FWIW, I had converted my Cayman to GT3 rotors and calipers and would go through stock drilled rotors in less than 10 days with RS19 pads. I switched to AP and they've held up for 1yr and half. Although my wife drives it mostly now.

I ran RS19's most of this year and experience a lot of tapering. I flip them often. I've just switched to RS14 and will be watching the tapering. I will likely be trying some PFC 08s thanks to your feedback.

[TRAKCAR]

I suspected as much and don't think it's a fluke, same here but glad you are confiming it.
Most drivers are rather safe then sorry and replace them earlyish.

I have 2 sets of OEM fronts that I wanted both to run longer, but PFC insisted I try their pads with threir rotors, so now I have 2 sets of front OEM rotors with 15 days on them, not knowing how much longer they would have lasted.

My guess is 20 days until I fully creack them, knowing I have a backup set with me.
I fully cracked many rotors in my Mustang, I see no danger in it. Plus they usually crack during cool down.

I replaced the first OEM set, so I had that set as backup when I put new ones on the front and then I got the PFC rotors a bit earlier then planned, so now I have 2 sets of front backup rotors. The plan is to run PFC until the crack (I mean completely) and then do the same with the worst set of OEM fronts. Then I know how quickly, if at all the PFC rotors will pay off.

I do like non-driller rotors better because the feel the same weather you blow out the holes or not plus I don't worry so much about them. The holes cracking further just makes me a bit less confident that a solid rotor that has hairline cracks everywhere.

I never ran 19's so don't know, but I am very impressed with the minimal tapering of the pads, just due to pads!