Max Power

My rotors are 42 years old w/about 150k miles. How do you know when they need replacing?
I've done 5 track days w/ stock Pagid pads, ATE Super Blue. '66 912.

In the absence of cracking, how does one determine when new rotors are needed?

LVDell

You would need to get the specs for your car and the req's for rotor thickness. Then pick yourself up a micrometer and go measure those rotors to see if they are within (or not) tolerance.

schwank

That's awesome! Just the thought of some vintage rotors surviving that long including some track fun is great.

Take that cup cars!

M758

Well figure in the price of a set of rotors, pads and the tires needed for them and then the fuel cost to run the car and bang... there is the cost of an entire 944 spec car.

kgorman

+1 for www.frozenrotors.com. I have used them for a couple sets for different cars. I can't tell how long mine last for because I have not worn them out yet. 40 days or more on them now and they look just fine. I use Pagid Orange or Black or Hawk Blue pads.

mark kibort

I do 12 pretty hard races per season, and i change my rotors when the cracks get bad. usuallly, this is about after 5 weekends. pagid orange pads and zimmerman cross drilled rotors.
at about $200 for a set of rotors, and near the same for the pads, its not a bad deal.

Mk

Jay Gratton

I am coming up on the start of my third season on my 924S. The thing just doesn't use rotors. I will probably change them this year just to give me something to do on a Sunday.

kurt M

On my 912 I am still running the same set of front rotors since 1998 and the only reason the original rotors were replaced is one had a bad rust pitted area on it and at the time they were only $27 each. I am on my second set of PF 97 pads in front and still have the first set in back. Rear rotors are original and still in spec. I like to tear down and freshen up the motor every other year and thus my brake pads last longer than the motor.

Nader Fotouhi

As someone who has seen you drive, this is not a surprise because I know that you use all the motor and very little of the brakes.

DaMan-993TT

Does anyone have a definitive answer to what that value is? I have heard 2-4 m for big reds.

I change them when the cracks start to show. RS-19 front Blacks in the rear.

Tony356993

I would only get about 3 events on my front rotors using yellow fronts and black rears in the 993TT. I swithced this year to a slotted rotor (not floating) using the same pads and stock calipers. After 2 events (VIR and Summit) the newer rotors looks like they were a good choice. However, the ambient temps were low at both events so I'll hold off on the final judgement until I get one of those hot/humid days at the Glen or SP.

boqueron

I am quite worried... I must be doing something wrong...

I have 12 track days (!!) with my GT3 rotors with RS19 pads... And they are not finished yet..(??)

One of my track days is only about 250 miles (tracking 1/2 hour and resting 1/2 hour until the day is over..)

PS.- I am not the slowest of my GT3 pac..

Ed Newman

My front rotors (from 03-05 Cup) were lasting about 4 or 5 days, a bit less than the pads 6-7 days (pagid RS19). I just put on GT3R rotors (Brembo 2 pc floating slotted not drilled) and after 2 days they still look brand new. I am hoping to be able to get more than 10 days out of them. In some ways I have it worse than the Cup guys since I weigh 300-400 lbs more!

A930Rocket

Tony,

I have the 993TT rotors with the Big Reds on my 930. Where did you get slotted rotors? I'd like to try a set vs a set of rotors with holes.

Jim

BC

+1.