slotted and or drilled rotors

AndyF said

I used to sell a 13 inch conversion kits for Mopar cars that used an OEM Mercedes rotor. Those rotors had holes in them right off the factory floor. Porsche rotors also have holes in them. So if it is good enough for Mercedes and Porsche engineers then it is good enough for me. I'm pretty sure that the factory boys test the snot out of these parts so if the holes created cracks they wouldn't put these things on the high dollar cars.

Click to expand...

There's also a big difference between holes and slots cast into the rotor or machined into the rotor. The worse of the two is almost always the machined rotors as you're discontinuing the grain structure of the material causing stress risers (slots and holes are already a stress riser by themselves). My bet is that those Mercedes and Porsche rotors have their slots and holes casted in the rotor. For a street car you won't really get much added benefit except for looks.