kadeer

Hi everyone,
I have 36000 miles on the car, it seems I need to replace rotors. Is that normal, or people get more out of them.
The car has one day on the track, 15 or so autocrosses.

-Kadeer
95 993 C2

Mike J

I had 62,000 miles on mine before replacement. I replace the fronts because they were are the wear limit. The backs are not yet at the wear limit. However, the car has not been on the track yet so its all city/highway driving.

I am sure the autocrosses/track has some affect on rotor wear. What pads are you using?

kadeer

Mike,
I have stock pads.
Seems like rotors should have lasted me longer.
-K

tom97c4s

What are the indicators that you are are at "the wear limit"?

kadeer

Actually, I left the car at the shop for DE Tech inspection and they called me and said I needed new rotors in the front.

I need them to certify it, so I agreed over the phone as the event is this weekend.

Robin 993DX

[quote]Originally posted by tom97c4s:
<strong>What are the indicators that you are are at "the wear limit"?</strong><hr></blockquote>

Tom,

To measure the min. rotor thickness you will need to use a micrometer and measure the area of the greatest wear on the rotor surface (which generally is located on the inner and outter smooth worn band area of the rotor away from the cross drilled holes)

Min. thickness:
Front : 30.6 mm
Rear : 22.6 mm

Tom Trew

Kadeer - rotor life depends so much on the driver and use of the car that it is difficult to answer your question. With some track and autocross time, I think 36000 miles is not unreasonable.

As an example, my 97, which sees about 25-30 track days per year, used to consume 2 sets of front rotors each year. I then started using cryo treated rotors, added the AJ USA cooling kit, and learned to drive a little better and use the brakes more effectively, and now can get a full season out of a set of front rotors. They are toast at the end of the year though. You should look at rotors as expendables just like tires and oil.

Edward

Tom,

Which cryo rotors did you use and what did you pay, if you don't mind my asking? I just bought front OEMS but might consider others in the future if there are better. TIA

Edward

Paul

Not trying to start some big debate, but my heat treater tells me that Brembo spent a small fortune testing cryo'd rotors, and found ZERO difference between treated and non-treated. Your results may vary.

Paul

kadeer

Robin, Thanks for min value. I was 30.6mm. Do you know they start of at new?

Tom, twice a year and 25-30 events, you must live on the track. I wish I could do that, the events, can afford that many rotors. Thanks for the input.

-K

kadeer

Ops, I meant "Can not efford that many rotors"

Ray Calvo

[quote]Not trying to start some big debate, but my heat treater tells me that Brembo spent a small fortune testing cryo'd rotors, and found ZERO difference between treated and non-treated. Your results may vary. <hr></blockquote>

Tend to agree; from my experience this year, I don't notice much of a difference between stock and cryo-cooled.

Tom Trew

Whether cryo treating adds to the life of the rotors or not is one of those issues that is hard to resolve. My personal experience says they do indeed last longer, but becuase I also added cooling ducts at the same time I converted to treated rotors, I have no real back-to-back comparisons.

I buy my rotors and pads from Weston Motorsports, 888-558-0631 (no affiliation, just a satisfied customer). The rotors he sells are Zimmermans, which I am told is the manufacturer of the OEM rotors. Cryo treating adds about $50 to the cost of each rotor, for a total of about $150 each.

Greg Fishman

I used to use the cryo rotors also and didn't tell any difference for the extra $$. I usually do about 12-15 events a year with several races and a front set will last the season, rears about two. I just use the factory ones.
Greg