Hey all,

I'm looking for a little help here. Been researching some options and just trying to get some feedback from you road course guys out there and other hardcore drivers.

My racecar is going to be in need of new rotors shortly. The setup right now is custom made Coleman Machine 13.9 x 1.375" rotors. Custom aluminum hubs of unknown origin. Custom made caliper brackets by previous owner / current owner. WIlwood SL6R calipers (from older Cup car I believe). Carbotech RP2 pads. WHeels are C5 Vette Magnesium and also ZR1 replicas. Using 2.5" alum. wheel spacer currently to get proper track width / clearance etc.. Calipers are made to fit super tight to rotor which is how I get buy with 17" wheels and 13.9" rotors, plus the spacers move the wheel out away from the rotor / caliper which increases clearance due to tape of wheel.

The rotors are hard mounted with bolts to a flange on the hubs (not a great setup to my way of thinking). 2 3" brake ducts to each wheel with appropriate shielding to funnel air into center of rotor.

Car is not over 3100lbs raceweight (me included). 275 width tires all around (class limits for American Iron). Car is currently running TTU with NASA due to budget constraints.

So far I have had no issues with brake fade. I have had issues with the aluminum hubs not retaining the bearings races when they get to race temps. So I'd like to put some steel hubs on there . . . job # 1.

Job #2 : The rotors from Coleman are about $200 EA after stress relieving etc., so it would be nice to find a cheaper alternative if that's possible. They have put up with a lot, the rotors have been just fine, they are just nearing the end of their life.

So, Corvette comes to mind. Seems like the Z51 C6 rotors at 13.38" dia and 1.26" thick might be pretty good. The Grand Sport / ZO6 rotors at 14" and Camaro SS at 14" I think would be pushing my space constraints a little too hard. Not going to 18" wheels, race tires in that size are way more money = wrong direction.

So, if we assume that the Z51's are perhaps a good option, the next question is : Can they put up with track duty? Obviously they are a 1 piece rotor with I think puts more stress on them during heat cycles, which it seems would lead to earlier cracks and ultimately earlier replacement. On the other hand, the rotors can be had from Rockauto for like $50 ea. So that's 4 sets of Z51's compared to one set of Colemans.

I would use my existing SL6R calipers and run .800 " thick pads, which last forever.

Anyone care to weigh in on which setup would be preferred?

Buy more Colemans (and still have to figure out new hubs somehow)
or swap to steel hubs and slap on the Z51's and change caliper brackets as needed?

Thanks for any thoughts and advice out there.

 

A couple pics of existing brakes / hubs