Originally Posted by GXP Venom
Drilled rotors in the early days were just the old school cast iron ones, But these days (from R1 Concepts page): Unlike the materials that were used in the past, several metal alloys are available in today’* industry that are hardened previously and can withstand thousands of degrees in temperature.
When the fad first came out, there were alot of them fracturing. I frequent quite a few forums and have never read a reference of an R1 coming apart. Some pricier ones are now cast into the rotors.
There was a massive thread on ls1tech a year or two ago where the consensus was that there is no performance gain to be had, and that even with hardened alloys, these can crack under heavy track use. Naturally this isn't an issue as nobody track races a Bonneville, and drag racing doesn't count. I remember seeing a picture of a Porsche rotor that was cracked, but that rotor had more holes than a speed limit sign in the boondocks.
I can't say anything bad about them though. I don't know if they actually do help cool the rotors down or if its just a gimmick. Yes they are noisier, but I personally love the sound of that drill sound (similar to a cordless drill) when I'm braking.
2005 Pontiac Bonneville GXP - For Sale ----- 1995 Buick Regal GS(X) - L67 madness
2000 Buick Regal GSE - Stock...for now
----- 1987 Jaguar XJ-* V12 - 12>8