Originally posted by mycainsbroken:
i know their job is to cool the brakes.
The point of holes in the rotors is not now, nor has it ever been, to "cool the brakes," but to expel gas released from the brake pad at extremely high temperatures--a phenomenon known as "outgassing." A bit of heat sink mass (cooling efficiency) is sacrificed to solve a very specific problem encountered by race cars on track. (Everything is a compromise.)
The other thing sacrificed is pad and rotor longevity. But, hey, as long as it gets us through this race, and saves us a few tenths per lap, it's worth it, right?
With modern pad materials, outgassing is less of a problem, even for race teams, and crossdrilling has proven to be less than optimum. Slotting achieves the same gas management objective, helps keep pads "clean," and offers less risk of rotor cracking. Still, when you look at most race series, the cars typically run either smooth-faced or slotted rotors.
Function before fashion.
'96 Contour SE
"Toss the Contour into a corner, and it's as easy to catch as a softball thrown by a preschooler." -Edmunds, 1998
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