Quote:
... Wilwood would not sell drilled rotors if they were no good. .....
Sure they will. They're in the business of selling brake parts. Enough people ask for them and they'll sell them. Actually, having worked for them at that time that is exactly what happened. They didn't sell them because it was unnecessary, but they got enough "tuners" asking for them that they saw a market, did some R&D and started offering drilled rotors.
The time for drilled rotors has passed. The original reason for the holes was to give the gasses generated from the friction material a place to go rather than creating a barrier between the pad and the rotor.
Modern friction materials do not out-gas like older pads (Ferodo DS11's anyone?).
The holes also had an unexpected side-benefit in that pads that really needed to be up to temp to work well tended to warm up slightly faster with drilled rotors. It was subtle, but with a good and consistent driver you could see it in the lap times.
Chamfering the holes results in holes that now have two sharp edges per side rather than one. Notice that the wilwood rotors are radiused. That isn't an accident.
I used to swerve around my hallucinations, now I drive right thru them.
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