crack limit on discs

[jhg41977]

1996 Porsche 993 C4S, street/track (DE) use.

Front discs are from Colman Racing, 6 slots, factory hats. I run Pagid yellow 19s on the track and Textar on the street. The discs have 16 DE days on them (LCMT, Glen, LRP and NHMS) probably about 15,000 miles of street.

I am approaching the depth of the slots which I am told is cut to the wear limit of the disc. I had planned on replacing after another three day event at LCMT. The heat cracks look bad to me but non extend to the outer or inner edge.

Im not trying to pinch pennies, if they need to be replaced before another event, I will do so. I dont want to waste money either.

[wildcat077]

Sure look like they've seen better days ... the next three day event at LCMT is in August,i wouldn't take a chance of having brake failure 12 hours away from home !

I went through two sets of front 996TT drilled discs which had severe cracks with my 911 before going with Sebro slotted units.

Cheers
Phil

[bw993]

What's the Colman Racing part number for the rotors that you are using with your C4S?

I would like to get the same rotors for a C2S.

Thanks,
Bill

[cstreit]

THat looks fine to me. When they start getting close to the edges, then replace them. All my Non-drilled front discs look like that after a few sessions...

[Eagledriver]

Originally Posted by cstreit

THat looks fine to me. When they start getting close to the edges, then replace them. All my Non-drilled front discs look like that after a few sessions...

Ditto

[cstreit]

Plus they are Colemans... Colemans are a bargain brand. Fine if you replace them often but they aren't a high quality disc....

[fredmeister]

Originally Posted by cstreit

Plus they are Colemans... Colemans are a bargain brand. Fine if you replace them often but they aren't a high quality disc....

Hey Chris,
I had heard before that Coleman was not a good quality choice. Something along the lines that they wear quickly. However, they are the only supplier that I have been able to find that will custom make rotors to fit my floating 930 front rotors. Zimmerman the OE supplier want $400 per rotor for my fronts....which is way out of my price range.
Can you provide a name or contact information on a good source besides Coleman so I can call and see what they would charge for good slotted floating rotors for my 79 930?

Sorry to high jack the thread, was not my intention.

Thanks,
Fred

[Bill Verburg]

Originally Posted by jhg41977

1996 Porsche 993 C4S, street/track (DE) use.

Front discs are from Colman Racing, 6 slots, factory hats. I run Pagid yellow 19s on the track and Textar on the street. The discs have 16 DE days on them (LCMT, Glen, LRP and NHMS) probably about 15,000 miles of street.

I am approaching the depth of the slots which I am told is cut to the wear limit of the disc. I had planned on replacing after another three day event at LCMT. The heat cracks look bad to me but non extend to the outer or inner edge.

Im not trying to pinch pennies, if they need to be replaced before another event, I will do so. I dont want to waste money either.

Thet are fine, worry when the cracks get to the edges

do watch the hats they will eventually crack, friend uses that setup drives very hard/fast gets ~2 annulus changes from a hat



Girodisk is a good alternative, they also use Colman annulus but the floating hat seems to add a lot of life and is lighter. I have over 5k track mi on mine, about 20% through the second set of RS29s(which have better bite than the 19s)

[cstreit]

Fred i can see what i can come up with. Most of the solutions i offer are pretty high end and would require custom hats.

The only reason i would recommend using Coleman is if you plan on replacing them a lot. Ive seen too many failures that caused a lot of incidental damage. Girodisc has a lot of Porsche people on board and frankly im surprised. we usually expect the best when it comes to braking and coleman is the opposite imo. i am a brake disc snob though...

[jhg41977]

Thanks guys, I replaced them with stock since it was all I could get on short notice. I think the Coleman are a good option. I got about 12,000 miles out of them I think. That includes 3 days each at Calabogie, Mont Tremblant, 8 days at Watkins Glen and two days each at NHMS and lime Rock. On the track I ran pagid yellow rs19.