slotted rotors: effect on brake pad wear?

[czo79]

Hello all...
Did a search, but not too much directly addressing this issue, with slotted rotors, how is brake pad wear affected? I am in need of front breaks, so I am getting cryo treated rotors and some hawk hps pads (probably, maybe axxiss ultimates or mintex) and can't decide about slotted rotors or not. Although the advantages are minor I guess, although I wonder if enhanced initial bite from slotted rotors might help with the little bit of weakness in some high performance street pads when really cold....
What do y'all think?
thanks
Micum

[LegacyT]

Slotted rotors dont do very much, just like drilled, their for show. If you want better braking get bigger rotors and a better caliper. A front WRX system is a pretty decent upgrade. In brakes bigger is always better, drills and slots, only lessen the braking surface, they can never make up for an actual larger rotor.

Mark,

[vrg3]

Mark - What are you basing that judgement on? It seems to me that a lot of respected tuners agree that cross-drilled rotors are mostly for show and can actually be worse than stock, but that slotted rotors can be good.

It's not clear to me why, though... From what I understand, most modern pad compounds don't outgas, so the feature of allowing gases to escape seems inconsequential. There is a slight increase in surface area, but it wouldn't seem like enough to matter. The continual de-glazing may be the only advantage. Going with this is a small increase in abrasive friction.

We should note that there are some slotted rotors which were cast with the slots in them, and some that had them machined in. I would imagine the former would be stronger.

The Subaru WRC cars do have slotted brake rotors:

http://weakycars.free.fr/galeries/x_jap ... oto_01.jpg
http://www2s.biglobe.ne.jp/~edoyama/imp ... /wrc01.jpg

My personal take on it is that the extra cost of slotting isn't worth the improvement (if there even is any). Stock WRX front rotors can be had for as little as $55 new, and even cheaper lightly used. Slots usually cost nearly twice as much.

[ciper]

I know for sure one difference between slotted or drilled over stock. If you listen to your car closely all the time you will notice that they make different tones of white noise. I have slotted drilled on the back of one legacy (they where free) and the noise makes me crazy.

From the research I have done I personally feel that slotted rotors on the front of the car help. I think rotors with holes should be avoided.

Instead of discussing this, we should speak about higher quality rotors with better venting. I say there isnt much better than the DBA kangaroo paw rotors.

[Legacy777]

I've got slotted....mainly got them due to the fact I wanted the slots to help against pad glazing. Outgassing of pads now a days is less of an issue....initial bite might improve a little....but wouldn't expect it to be leaps and bounds.

[silverturbo]

Aren't the slots to help get rid of the water off stainless steel rotors?

[Legacy777]

nope....that's not the purpose.....at least on car rotors.....they are just cast iron....not SS.

[ciper]

Some car has stainless steel rotors? Id hate to replace those when they wear out!