Originally Posted by Maxwell
actually I believe the cross drilled rotors are not designed to remove gasses even though they do have that effect, but the real reason for drilling out the rotor is to remove excess rotational weight from the car's driveline. this is only necessary for full ***** to the wall race cars who are trying to shave off every ounce of weight.
I doubt drilling perhaps 100+ 1/4" holes in the rotors would amount to any significant reduction in rotating mass. Also who in their right mind would choose to lighten (hence weaken) their primary safety system??? It is known that there is the possibility of cracking rotors at the drill points due to extreme driving conditions.