How does drilled rotors give better performance?

 

Since they're vented, they stay cooler, also with the holes going through the rotor, any air or gasses that get trapped between the pad and the rotor, escape through the holes allowing for better pad contact to the rotor.

 

From Baer racing... makers of great braking systems:

Q: I don’t want to spend the money for a complete brake upgrade. Do you offer cross drilled rotors to work with my factory brakes?

No. Baer Racing is in the business of building brake systems that will noticeably improve the braking performance. Although there are those that will sell cross-drilled rotors as a performance upgrade, the testing we have done indicates there is little, if any, improvement to be had by simply cross drilling rotors.

Cross drilling was designed to alleviate a problem known as out-gassing. In some of the older pad compounds, when the pads reached elevated temperatures consistent with performance or racing use, the binder (that’s the material that holds the friction material in place) boiled off, producing a gas. This gas would build up between the rotor and the brake pad, effectively keeping the pad away from the rotor. The holes provided a relief path for these gasses, so the pad could once again contact the rotor. Cross-drilling was NOT designed to facilitate cooling.

Although Baer offers cross drilling as an option on their systems, it is offered as a cosmetic option only. Furthermore, it has been our experience that cross drilling will shorten the life of the rotors.


-Shing

 

Granted, this is a 'seat of the pants' opinion and I have no data to back up my claims.....

My Stillen cross-drilled rotor/Axxis pad setup was sweet, with what felt to me like race car braking. If you hit the brakes, to quote JimW, "it feels like a boat anchor has dropped out of the back of your car".

Now, in the past I've run Axxis pads on regular rotors on the Max and did not feel as 'boat anchor' confident as it did with that Stillen setup.

The main disadvantage to this was that there was no such thing as smooth application of the brakes......if you wanted to stop, you stopped. There's no in-between.

I enjoy my current setup, and will probably never go back to cross-drilleds. Mine lasted 30k, but they can't be turned.

Granted going with a more racing-oriented street pad like the Porterfield R4S pads and plain rotors will probably yield boat-anchor stopping power without the need and expense of cross-drilled rotors, but if you want them for a 'look' then they are worth a look.

Otherwise, go with Porterfield pads and rotors.....

hehe.....now I'M flaming Shing...

 

I've tried axxis on slotted and regular rotors. Doesn't make any difference. The slotted looked really cool, but stopping wise it didn't help. I think what you are feeling are new rotors vs old, rather than drilled vs not drilled. I mean there is more friction surface with a non slotted/drilled rotor, so I would think that the advantage would be to the non drilled rotors.

-Shing

 

I would say it 'felt' like I had stainless steel brake lines (even though I don't), in that the braking was much firmer/harder with the cross-drilled rotors.

Now, I'm not sure if it's just the initial 'bite' that I felt or what, but that translated to me thinking that the car actually stopped shorter.

My comparison (although I'm going from memory) was based on the 2 times that I replaced my brakes, once with cross-drilled rotors and the other with regular rotors. Axxis pads were used both times. So, everything was new both times.

Raging flames now....

 

So how does brake fad work into this whole equation? Because i know whether you have stock pads or upgrade pads fade is still a problem. So does drilled or slots help brake fade?