I_am_imprezed

How come fronts for our cars are only like 55 a piece but the rears are like 95!? does anyone know a cheaper place to get oem rear's? if not i'll prob just get zimmerman's since they're only like $15 more.

racer

While I don't know the exact reason, it is possible that the Front rotors are used by more than just a Porsche 924s/944.. maybe BMWs and VWs and Audis too.. whereas the rear rotor may have fewer other uses, thus is not produced and sold as cheaply.

whalebird

E brake drum adds heft.

Travis - sflraver

I will sell you the rears (zimmermann) for $75 each...

Fishey

Ok, this is a bit complicated...

Anyways, first here is the part number you need is CW20112

Call TireRack and tell them you would like to order 2 of those..

Reasons why
1. Zimmerman rotors suck
2. ATE Rotors rock
3. They are cheap

= WIN!

http://www.ate-na.com/generator/www/...rotors_us.html
These rotors are better then ANY others on the market for factory fit. PERIOD.

Jim Clark

E-Brake engineering...........!

Travis - sflraver

"fit" aside, zimmermann rotors do seem to hold up much better than the ATE ones when pushed to the edge.

https://rennlist.com/forums/7029340-post52.html

whalebird

get the lifetime rotors from autozone and trade them in before each track weekend.

I_am_imprezed

So can anyone who has ran both the ATE's and Zimmerman's give me proof of why one is better than the other. The $75 a rotor deal sounds very tempting and unless i can get ATE's cheaper i probably wont get them.

Fishey

I have never seen anything like that on a ATE before and I worked on a TON of 944 track cars with them.

I have seen Zimmermans fail at the hub and crack throughout the face of the rotor. However, I have never in all my experience seen a crack like that in a rotor. Usually, you get face cracks before you end up cracking the rotor. That ATE rotor has Zero noticeable face cracks. I am very use to seeing failures similar to this regardless of brand. Simply you can only do so much with your base material.




The second most common thing I see in Zimmerman/Brembo failure is physical warp usually in the rear brakes not the fronts. (Altho, stoptech says its impossible)




That being said. I like ATE for the following reasons
1. They are coated so they continue to look nice over a long period of time. Also, since the veins are coated it seems to keep them rust free and flowing air better then rusted up veins you get as some other rotors get older.
2. They are slotted and while it really does very little for performance. Again I like the look and the wear indication
3. I have never had a problem with a single ATE Premium One rotor outside of the extreme. (As shown in my post picture 1)

I_am_imprezed

thanks. Alright ATE it is then!

Travis - sflraver

So the first pic is an ATE rotor which shows the start of a crack like in my link?
In the second pic, the brake pad doesn't apear to have ever touched a section of the rotor (no rust, looks new). Was it warped from the factory or just misaligned on the car?
Also, all zimmermann rotors are coated now (zimmermann coat Z). It is the standard. No pretty lines though.

TNT25169

I highly advise zimmermans. I know plenty of racers who have been pissed off with ATE "slotted" rotors like in the linked picture and cross drilled rotors. It is a well known fact that the best brake performance you get in terms of stopping is with a stock/full rotor. The surface area provides more to grab, although slotted and drilled rotors will cool better (this will lead to more heat cycles ie. cracking) they will also wear faster and warp sooner. So it's really a decision of what you want from your car. If you can afford to change your brake rotors every race I'd go with slotted or drilled but if you want brakes that will work in the dry with very few problems I'd get the zimmermans....just my 2 cents though....

Fishey

Actually, The first one is a factory corvette disk just showing how brakes normally fail. I posted it because I have never seen a disk fail without first showing face cracks on the surface of the rotor like in the corvette disk. The ATE picture you linked has no face cracks just one giant crack and that is very very odd. The second is after the brake was turned and the clean part of the rotor or "new as you said" are where it was able to hit. The "worn" parts are where the disk is actually not able to hit because of how uneven it warped under high heat load.

M758

Get the cheapo's.

For my 944 spec car I run the cheapo chinese front rotors at $30 each from Paragon. In the rear I was too cheap to buy rotors so I pulled some rusted & worn, but still in thickness rears off one of my parts cars. I cleaned the surface rust and slapped them on. I have been happy with both. Remember this is on race car that uses Hawk Blue pads and I beat the snot out of it. I have found no difference in the chinese types vs the zimmermans when it comes to braking performance. As for durablity my first set of chinese jobs might have lasted a little less than the zimmermans (thickness), but it is hard to say for sure. I mostly just run 2 or may be 3 sets of front pads to one set of rotors. Even so I got a second set of chinese jobs. My pads cost about double what my rotors cost so for my Pad life is more important than rotor life.

I would have no isues putting the chinese jobs on a street car.