Read an article that Nascar and the like no longer use drillled rotors due to cracking. Most today are bought for the cosmetic look.
Are they going to solid rotors or slotted ? I would like the slotted for cooling and looks but not if I have to worry about cracking, I will auto-X and don't want to take the chance...... Any advice, I haven't looked into any brake components as of yet.

Tripp

 

Racing with them is a waste. Porsche cast the holes in the rotors which seems to work better.

 

As John says cross drilled rotors are not effective. I am not sure that slotted rotors are much better.

If all you are doing is autocrossing brake cooling improvements are not going to help. In the typical Low Speed Autocross (run time from 40 seconds up to 1 1/2 minutes and max speed between 50 and 80 mph) you do not get the brakes hot enough for additional cooling to make a difference.
Bill

 

Do not put Drilled rotors for your car if you are running at the track! You are wasting your money. This time I went with the Plain old rotors,

no drilling, no slotting, or no zinc plating... These new rotors will last the longest. :)

vetterdstr :cheers:

 

One of the ways to ruin a BMW yuppie's day is to see his car on the track, for the first time, and point out all the little cracks froming in his gazillion dollar hand made alpine old world crafted rotors. Cross drilled rotors were sort of a good idea when they were single plates. And they do look nice.

 

Thanks for all the advice....... :chevy

Tripp

 

I got mine for looks so there..... :smash:

 

Sorry, but i cannot agree here. My stock rotors where terrible cracked after 13000 Miles. They where warped and not to use anymore. Then i changed to the x drilled/slotted BAERS. I cryo treated them before install. After 15000 Miles of hard driving (Even at 175 MPH on Autobahn) i can not find ONE crack and NO wrapping. I guess i will use them at least another 13000 Miles - They look great !

Jochen

 

What temp did you take them too, and for how long ?
This is a new one on me.....
:smash:

 

I like the cross-drilled and slotted rotors too... BUT... can you get them resurfaced when its time for a brake job or just throw them away. I want to upgrade but I don't want to waste cash on a onetime deal.

 

evil1, in germany i only found one cryo company. Usually they treated only working tools, but since a few years they work together with the motorsport industry and they cryo almost everything you can find in this industry (cylinderheads, cams, valves, brake rotors . . .).

The cryo job they used on my rotors took several days. It was a computer controlled cooling, step by step down to minus 182 degree Centigrade (not Fahrenheit !). before the cooling, the rotors got heated up to 150 °C. The complette process is a very slow procedure so the rotors will not get cracked.

darkmercury, yes you can resurvace drilled rotors even when they are cryoed before, The drilling does not make resurvacing more difficult. After my first set of stock rotors i used drilled rotors from my cardealer. They last almost 18 000 Miles with no cracking. After 18 000 Miles i felt that they start to pulse and get warped. I changed to the BAERS and let a shop resurvace the old drilled ones. They where just very little warped, so the shop took them on a late and resurvaced them for 30 US$ :D (One stock rotor in germany is more than 130 US$)

I still have the old, drilled ones conservated in my garage. I will use them again when the BAERS get warped. I spoke to the shop, they will turn the BAERS too as soon as they are warped.

Jochen


[Modified by Jochen, 5:13 AM 7/6/2002]

 

I have a buddy (SPDY C5) that ran the 2 day session at Road America with speeds in excess of 165 MPH and hard braking. His EradiSpeed rotors were fine. He did go through a set or HAWK HP Street pads. His front calipers got so hot the Folia-Tec paint turned brown.

He turned the rotors installed new pads and his as good as new. So I wonder what sort of enviroment will ruin these rotors?

Tom
USAF Retired

 

Not to change the subject but where, on Road America, did he get up to 165 MPH?

 

Must have been one of them new all wheel drive 700HP Godzilla Vettes with stock brakes :rolleyes: :rolleyes: :rolleyes: :rolleyes:

 

Richin Chicago
I hear it's a fantastic place.
Elkhart Lakes, Wi. http://www.chasinracin.com/track-locator/usamap/wi/ http://www.roadamerica.com/

 

:

Jochen : I use cryo for patients to control post op pain but didn't realize there was a benefit from it on car components/live and learn... :cheers:

Thanks
Tripp


[Modified by evil-1, 12:09 PM 7/6/2002]

 

I was talking to a friend a couple days ago about this same thing (cyro break rotors that is). He has a M-Coupe' and said that quite a few guys on the M-coupe board have done this.

check out the web page http://www.frozenrotors.com/cryo.htm

It is interesting at the least and worth a thought :yesnod:

 

I'll check the facts again but that's as I remember him telling us. He's pushing 442 RWHP and was running his BF Goodrich racing slicks. But the bottom remains, under what conditions will these rotors fail? His two days at RA wasn't sufficient to cause any damage regardless of absolute top speed in excess of anything short of running a full 300 mile road course at race speeds. This was about as tough a place on brakes as you can find. That's all I was trying to say.

In any event I'll have Joe check in with the details.

Tom
USAF Retired

 

They will play "connect the dots". My 89 did so after street driving in one Phoenix summer. Spot milled like the GT Rotors seem to be holding up for me so far. Never again will I use cross drilled. :nonod:

 

Uhh, correct me if I am wrong but I believe that cross drilling was originally done to relieve the build up of excess gasses between the rotor and the pad which severely reduced braking abilities. This is no longer a problem with todays compounds and so the verdict is that crossdrilling looks cool, but is a waste otherwise. :cheers:


[Modified by rrobert22, 9:18 PM 7/6/2002]