At 03:40 AM 11/06/2002, you wrote:

>I am no expert, but I thought the whole point of cross
>drilling was to dissipate heat.
>
>Thanks,
>Chris

That's the theory. It was tested quite thoroughly by Porsche and others at
Le Mans some 30 years ago. After sorting out the problems, they went back
to vented solids, more mass, with custom cooling air ram ducts pushing huge
quantities of air at speed directly into and through the rotor vents. The
76 BMW R90/6/S came with drilled rotor, stated purpose to shed water for no
suprizes in the rain. Any better cooling going on is offset by the mass
lost to holes. It is mostly just a claim blown out of proportion to sell
the drillings.