Need new ROTORS!!! cross drilled or slotted???
 

Hey, just wondering what everyones opinion is on this...im in need of new rotors and cant really decide what to go for...which is better performance wise....they are both the same price...so im not sure which one to get....
thx in advance....

Both perhaps? I am using Brembo cross drilled & slotted for almost a year now with no problems. They seem to work really well.

cross drilled rotors are old tech. the reason cross drilling came into practice in the first place was to alleviate gas pressure which would build up between the pad and the disc under conditions of extreme heat. The problem with cross drilling is that it creates a disc surface which cools unevenly and eventually leads to cracking. It also reduces the surface area of pad contact which results in slightly less efficient braking performance.

Slotted discs are a more recent development which alleviate most of the problems with cross drilling (cracking and reduced disc surface) while still allowing for any hot gasses released by the pad to escape through the channel in the disc. There's also discs now which are both drilled and slotted - slots for gas release and holes drilled to cool the discs faster.

Honestly - on the street you aren't likely to encounter either of these problems unless you drive like a total nut. If you track your car a lot then they are a genuine concern. And besides, most pads these days don't release gasses anyway.

another thing - beware of rotors which are drilled after they are cast. Some cheap cross-drilled rotors are done after the fact instead of being cast with the holes in place and this weakens the rotor a lot - these will be more likely to crack on you.

Just to mix things up for fun, 85% of my driving is on the track. I use'd the plain old stock rotors with porterfield pads for the last two years, and I've never had any brake issues other than a little brake fade once or twice. Who needs cross-drilled or slotted? :D

I would recommend getting ones that are cadmium coated. I have the brembo cross-drilled/slotted rotors, and while I haven't had any problems with them performance wise, they have surface rust on the "hub" area. it doesn't look very appealing. there are many debates on this subject already on the forum. you can probably find out any information you wanted to know. just search for it. :)

what ever you get, why not get them frozen. It seem to make sence but i have never had any experience with getting them frozen. anyone got any experience with this that can comment on if its worth it or not?

I haven not personally had my rotors cryogenicly(sp?) treated, but I have heard good things about it from multiple sources.

why are the slotted and drilled rotors cheaper than the just slotted or just drilled on rx7store??

If you want performance get blanks. Cross-drilling/slotting will not help with braking performance. It is merely for looks these days. If you want better performance get some higher friction pads and some stickier (or wider) tires.

Cryo Treated Rotors
 

I have used cryo treated rotors on two cars now and have yet to warp a rotor. On my 3rd gen I've gone through 2 sets of Hawk Blacks and a set of KFP Gold on the front rotors and have had very low wear.

I have a local source that'll cryo a set for $50. If it cost more, I probably wouldn't get the cryo treatment. All that science is pretty subjective stuff, plus you have to buy quality rotors. I also use a torque wrench on the lug nuts like religion and don't set my parking brake when the brakes are warm.

Whats the word on dimpled & slotted rotors?

whatever you get, put a clear coat of high temp pain on the hub to keep them from rusting. I used a clear coat that goes on motorcycle exhaust pipes.

On my to be Mods list I think I'm going with the M2 big brake set.

Talk to GoodfellaFD3S he can tell you who to talk to about buying a set of rotor's that are cross drilled and slotted for around $280.00