I'm thinking of upgrading to slotted or cross-drilled (or both) rotors to fit my OEM front brakes. I plan on tracking my car another 5-10 times this year, and am hoping for some feedback regarding the advantages I can expect from upgrading the front rotors only.

Should I get slotted or cross-drilled or both?

Do they have to be cryo'd to be real strong?

Will they prolong pad life or shorten it?

What's the effect on heat?

Is it a dumb idea to keep the rear stock rotors while upgrading only the fronts?

Thanx!

 

The stock rotors work fine. Eventually you'll have to replace them and they are probably cheaper than the cross drilled or slotted rotors. I'm not sure if the crossdrilling or slotting helps braking performance... Correct me if I'm wrong, but I believe that if you want to increase heat dissipation, you increase the rotor size.

 

Don't get cross-drilled. Since CoralDoc pointed it out, I've been checking cross-drilled rotors at the track, and many (most all) of them had small cracks starting around the holes. They're fine for street driving, but you'll probably be replacing them sooner than you'd like if you track them. Just get slotted. You can use the stock rears with upgraded fronts; that's how the Wilwood kit works. Not sure about pad life, probably depends more on your driving style than the rotor you use. There are pads that are hard on rotors; not sure about the reverse of that.

My stock rotors work great for me, but you'll need to replace the stock fluid with ATE or Motul for track days.

 

If you drill and/or slot the stock rotors, you'll only hurt yourself - unless you plan on replacing them after every season, maybe sooner.

It's possible to get purpose-made slotted/drilled rotors that'll hold up, but that won't help unless they're significantly lighter (either some exotic material [cost!] or less mass [more prone to overheating and general failure]) or you do a proper caliper upgrade at the same time. (Which most likely would require a wheel upgrade too.)

You best bet? Just take care of your regular stock rotors. Let them properly cool down the last lap of the session and don't ever use your parking brake between sessions. Check them periodically for cracks and warpage.

Judging by your track experience, you'll probably see absolutely no difference by changing rotors. Heck, I've been doing this for several years and I doubt I would either. Once thing you can do that absolutely will be noticeable and a big improvement is to get some proper track pads, such as Porterfield R4S or Carbotech Panther Plus.

 

I use SuperBlue fluid and currently am favoring the Brakeman #3 front / Axxis Metal Master rear pad combo. Thanks for the tips. Any more?

 

Bad idea. Both slotted and drilled.

Stick with stock rotors. I know docomind is talking about a 2 piece rotor that works w/ the oem caliper.

 

Cooling has been a problem for some people. I haven't had any personal experience with the issue, but some ducting for the fronts has helped. I've yet to hear of a good solution for the rears, however, since they're not vented.

 

here...

read this

http://corner-carvers.com/altimathread.php.html

 

I used to have cross-drilled rotors, and they warped after one track session. Also with dusty pads like r-4's the brake dust just accumilated in the holes and clogged them up.

 

I agree that there's no real performance benefit to slotted/driled one piece rotors, and reports that they crack and reduce pad life.

Things that might help:

two-piece rotors (lighter, better heat management?)
directionally vaned front rotors (better cooling)
brake ducts (better cooling)
better pads (consistency over temperature range/ability to handle heat)
better fluid (ability to handle heat)

Ted