[84FordMan]

When it comes to slotted/drilled rotors there are two types that determine quality and reliability. You have ones that have been cast, when the rotor was formed, it was formed in a jig which formed the slots/holes with the rest of the rotor, your major brake manufacturers do this. Then you have those who just buy rotor blanks and then drill/machine the holes/slots into them, this severely compromises the metallurgical structure of the rotor, this is why you hear people who say they see cracks radiating from the holes of cheap drilled rotors:

Pads do not gas out, not since the ban on asbestos linings. Cross-drilling and slotting removes material from the rotor, making them lighter and when it comes to the most bang-for-the-buck in weight reduction, reducing unsprung mass nets you the most reward and, well, rotors happen to be unsprung mass. This is the only benefit to cross-drilling or slotting rotors.

A rotor's job is to take the friction from the pads, which translates into heat and dissipate it. When you remove material from the rotor, what do you think that does to it's thermal conductivity? Yeah, lessens it. You are more likely to experience brake fade and that is a fact unless someone wants to challenge the laws of thermodynamics. B)

 

[84FordMan]

Brake fade - Wikipedia, the free encyclopedia

HowStuffWorks "Drilled Brake Rotors"

Your logic is sound, but not your conclusion.

I don't see how, both of your links dictate that extreme temperatures of either the pad/rotor or fluid within the caliper are the root causes of brake fade. Which leads to the development of air vents for brakes, 'turbine-cooled brakes' for the Veyron or brake pad heatsinks.

Also the links do not recommend crossdrilled rotors for anything outside of street duty, if racing they recommend slotted if not blanks. HowStuffWorks seems to imply that some people do extreme driving through car washes thus they should equip their car with crossdrilled rotors :lol2:

Also when have you ever seen a major brake manufacturer NOT recommend selling you the more expensive crossdrilled rotors? StopTech does just that:

'StopTech provides rotors slotted, drilled or plain. For most performance applications slotted is the preferred choice. Slotting helps wipe away debris from between the pad and rotor as well as increasing the "bite" characteristics of the pad. A drilled rotor provides the same type of benefit, but is more susceptible to cracking under severe usage. Many customers prefer the look of a drilled rotor and for street and occasional light duty track use they will work fine. For more severe applications, we recommend slotted rotors.'