chris walrod

rotor paint is a great indicator to temperatures. check it out:

Ed Newman

I am not having problems with boiling SRF. The SRF has allowed me to take the brakes to their limits. If I am fading Pagid Blacks, my understanding is the temperatures are passing 1200 deg F. I think the problem is both underbraked and under cooled. It goes back to HP and weight and no good way to get cool air to the brakes. The front of the car is all radiator and no good place to get a duct to route air through a hose. The cup car ducts that I have just scoop some of the little amount of air under the car. They are only mildly effective.

chris walrod

I wonder if removing the backing plates will help?

George A

Chris, where did you get the rotor paint? How does it work?

George

Mike in Chi

Ed

The other way to build very high temperatures in brakes is to slowly squeeze the pedal down during high speed braking.

Feels more controlled to the driver, but generates much more heat.

JC in NY

Yes! This, in my experience, is the one of the biggest problems with Porsche brakes.

Not saying it's definately your problem Ed, but in general Porsche brakes are overheating thru user error.

Ed Newman

LOL, you've never been in the car with me. I tend to be more of a late braker. But this does bring up a point with the ABS. On ceratain tracks and surfaces, I have to brake earlier and longer because the ABS kicks in. I wonder what effect this has on heat generation?

JimB

Ed,
I had a similar experience when racing my 996 with Pagid Blacks. First, I was always in the ABS causing me to brake earlier and lighter and second, overheating problems. I went back to Oranges and the problems went away. I'm pretty convinced that Oranges are the way to go on the 996.
Jim

chris walrod

George, I 'borrowed' rotor paint from work. I am sure many racer supply houses offer it.

After three autox's and a one-day DE, I just barely started to burn off the green, which is at around 550 deg. F.

I guess I am not braking hard enough?

George A

Thanks Chris, now I have to go find some. I think I'm over heating them and want some confirmation.

George

Ed Newman

Maybe I'll give the oranges a try. It depends on the track. At Pocono for example, I do not engage the ABS at all, where Limerock it is always in the ABS. Probably just a surface grip difference, but I hate to give up the advantage at some tracks.

Greg Fishman

Ed.
What kind of suspension do you have? Do you have a compression adjustment?

JimB

Good point Greg. Ed has both rebound and compression. It might help to take some weight off the front under braking.

Ed Newman

For now, the Porsch X74 which is quitye soft for the track. I have a set of Adjustable Motons on order with cup car spring rates. That should help some.

chris walrod

Looking through my notes about rotor paint:

Following are the temps in which they burn off:

Green 454C / 850F
Orange 555C / 1025F
Green 610C / 1130F

I know this is trivial, but then again we are all trivial