Does anyone know if it's safe to cross-drill the stock front and rear brake rotors? If so, does anyone know of where I can get this done and about how much it might cost? Any input is appreciated. Thanks.
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No,it is not safe, since each hole is a stress riser in cast iron rotors. When the rotors heat up during hard braking, thermal expansion causes microcracking to start at the edge of even well-chamferred holes. Unless, of course, you never drive the car hard enough to heat the rotors up enough for thermal cracking to occur. Said another way,its cosmetic.
As a test, ask your supplier to guarantee, in writing, that the rotors will not crack, or they pay all damages resulting from an accident involving a cracked rotor. I once published a story based on an SAE report by Ford Motor Company detailing the brake development in the LeMans GT-40s. After nearly a year of work including building a LeMans simulator for the brakes, Ford Engineering with all their resources, could not get their drilled rotors to stop cracking. The desperation- fix was--- quick-change rotors! Every 2 hrs during a fuel stop, they swapped out all 4 rotors, most of which were in the early stages of cracking. As we know, Ford won LeMans 4 successive times but who knows how many rotors were trashed...
As a test, ask your supplier to guarantee, in writing, that the rotors will not crack, or they pay all damages resulting from an accident involving a cracked rotor. I once published a story based on an SAE report by Ford Motor Company detailing the brake development in the LeMans GT-40s. After nearly a year of work including building a LeMans simulator for the brakes, Ford Engineering with all their resources, could not get their drilled rotors to stop cracking. The desperation- fix was--- quick-change rotors! Every 2 hrs during a fuel stop, they swapped out all 4 rotors, most of which were in the early stages of cracking. As we know, Ford won LeMans 4 successive times but who knows how many rotors were trashed...
Thanks, Jack. I'll certainly wait until I upgrade my entire braking system for the cross-drilled look.