Originally Posted by sorestgore
yeah, i know the holes are for cooling functions, i've been doing SCCA and road rally events since i could drive, lol, but the purpose of the slots is to keep the surface of the brake pad itself clean and at thier peak amount of grip, and it scrapes a minute amount off the pad to do so. this stuff is for brake pads that are hard, and can be resurfaced that easily.
wrong...wrong...wrong!
drilled and slotted rotors actually run hotter than a comparable vented rotor...the rotors are used as a heat sink to move the heat created in braking AWAY from the calipers. the more heat that ISN'T moved, the hotted the brake fluid becomes, and as the brake fluid heats up IT becomes less effective. by drilling and slotting the rotor you decrease the amount of metal the rotor has, lowering its mass and creating a smaller heat sink.
the holes are [were???]to remove gasses from between the pad surface and the rotor surface, which isn't a big deal these days. The pad materials that are used create very little gas anymore (unless you buy VERY CHEAP pads, but then why buy slotted rotors!?!)
the main reason for the slots are used to remove the glaze on pads (and clean, i guess)...but here again, we have a problem...where does all the material go that's being scraped off? into the holes.
ok, i'm done for now...