911 heathen do you know of any source for slotted rotors for a 965? I use these rotors and quit frankly can not find any source other than Porsche - options solid or drilled * cost $200-300 per rotor!!!

I did not see the comments about the groves. They are not the evident on the picture - at least not on my monitor.

Do you change out pads? What do the pads look like? Is it just one side of this rotor?
How deep is the "groove"- is is really grooved or uneven wear?
I would be more concern with the cause of this. caliper problems?

Don't know what pads you use, but others have used Hawk Blues to fix irregularities in the rotor. Those damn things are abrashive. Not very rotor friendly. But make sure you are comfortabe with the overall brake operation.


One last point, the fact that you posted the question and did as much research tells me your are concerned about safety. Let me just let it at that. Good luck and be safe !

try VCI

ecm911; try EBC for the rotors and pads.
I have a full list of their products in my PC somewhere; if I find it I'll email it on...

Of course always try our host but this link is a good resource

http://www.ebcbrakes.com/Automotive.html

Check these comments from EBC on drilled rotors, they slot and dimple theirs -

ADVANTAGES
The wider slot actually draws cool air across the pad surface keeping pads and rotors cooler. They also expel dust, dirt and hot gases better than fine slots which eventually fill with rust and scale and become ineffective in our opinion.
The blind drilled holes break down surface gases when braking from speed but do not weaken the rotor cross section as can happen with through drilling, thereby lessening the chance of rotors cracking over time and heavy use.

All tongue and cheek of course wastintime...good luck with whatever you decide.

-Jeff

ECM, thank you for that comment, the only reason I got offended by certain posts was that it implied I really didn't care about my fellow DE goers safety let alone my own. I didn't get up yesterday morning and say "how can I screw with as many people as possible at the DE?"

Just took the car off the lift... my boss and I looked at them again this morning and decided to run them. Especially since Roebling is so easy on brakes. Now, after each session I plan on carefully inspecting them, and if there is any big visible change, calling it quits. A catastrophic failure is pretty unlikely without any visible warning before it.

Actually, the rotor I posted is the Right Front, and the grooves really aren't that bad, they just looked bad because some pad material was smeared on them. The left front has very little cracking, but worse grooves... so who knows. Lol, the left front probably has another 3 weekends in it though which is the funny part. Mark @ frozen rotors was impressed when I told him how many laps I got out of them.

As far as getting away from cross drilled rotors... I do agree slotted might be nice, I use them on my WRX, but the crossdrilled have lasted this long, and if you break them in nicely they wear pretty nicely. Plus Porsche and Brembo usually know their stuff... And, for me at least Frozen Rotors sells 965 rotors pretty cheaply... $230 per rotor, they used to only be $205 though. Now those are 3.6L 965 rotors which are different than the 3.3L. I don't know if you guys were using the 3.3s At any rate, they're readily available, and they work... I know some guys that have run with super lightweight rotors and just hated them, so I'm pretty happy with the stock rotors. Besides it's not like I race this 911, it's just my personal car.

As far as pads are concerned I run PFC 97s in the rear, and Pagid Orange in the front usually... the combination works amazingly well for me. I'm running the Hawk blues in front at the moment just because I had an extra set, and they seem to be much easier on rotors, but they are really nowhere near as good as the Pagids. After breaking in the new rotors I'll probably go to PFC 97s in the front though. They wear the rotors a little more, but man... once you brake with them you'll never want another pad. I haven't been switching the pads out, for street driving, but I may end up running Ferodo street pads between track events.

Anyway, I'm off to the track!

So many experts....so many opinions.

I've got a 91 965. Your pic of the rotor looks the same as mine. As mentioned earlier, they start cracking right away. I also run Pagid and found the pads to be quite hard on the rotors....(causing the groves and cracking). With stock pads it's not nearly as bad.

My pockets are not deep enough to change them for every DE...

Well, I just got back... the rotors were fine, lol, they don't look a bit different after the weekend (yes, new ones are on the way anyway). I ended up having a great time actually, never had any problems at all, well except for the outside temp getting to 106 today. That sucked, and the track was too slippery for really good times. Still I managed to do a 1:25:33 (a personal best!) at Roebling saturday morning before the track got hot... that's not bad.

Re: How bad does this rotor look?
 

There you see the classic problem with holes in a disc. In my opinion, the only reason to run them is if there aren't solid discs available for the application.

To measure the grooves you need a point micrometer the min thickness in the groove well is 30.0mm f and 22mm rear w/ a max lateral disk runout of 0.05mm

as I stated earlier crackes of <7mm and not to the outer edge are w/i spec