zhenya

Porsche, like everyone else, ultimately does it for looks. What percentage of P-cars sold do you think actually ever see any track time? And if they do, the rotors are going to be changed to slotted or solid sooner than later.

Flyboy

Everything I've read about rotors supports what you're saying. I agree completely.

crew219

DRILLED VS SLOTTED ROTORS

For many years most racing rotors were drilled. There were two reasons - the holes gave the "fireband" boundary layer of gasses and particulate matter someplace to go and the edges of the holes gave the pad a better "bite".

Unfortunately the drilled holes also reduced the thermal capacity of the discs and served as very effective "stress raisers" significantly decreasing disc life. Improvements in friction materials have pretty much made the drilled rotor a thing of the past in racing. Most racing rotors currently feature a series of tangential slots or channels that serve the same purpose without the attendant disadvantages.

VelocityS4

drilled rotors shouldnt be on our 4 million lb cars

Alex (lil' is 300)

Thank you.

rojodosformula::red

sounds a little sketchy although ecs drilled and slotted rotors are machined from a solid rotor.

Bonarek

Pad materials have changed yes and the use of the correct pad for the correct application has all but eliminated off gassing, however: put a street pad to good use on the track or a few hard stop on the street and it can become an issue. Another benefit of cross drilling is water evacuation. Porsche rarely does something for the mere visual benefit of it and the mojority if not all of their rotors have cast holes in them. They're there for a reason, not just to look pretty. And you can check out the UUC brake kit write ups...they mention off gassing in their brake kits for some very modern cars.

zhenya

cars, even Porsches, that are regulars, have dumped the drilled rotors. They simply solve a problem that no longer exists, all while causing other problems that are still very much a reality. Talk to brake engineers who design this stuff. Talk to people who put together race cars. There is a concensus on this issue everywhere except among some in the enthusiast forums, where there is still a lot of misinformation floating around as truth.