New Rotors....Slotted and Drilled???

I have heard different opinions about why to have slotted and drilled rotors. One is that the drilled rotors allow more brake cooling. Another is that in the process of braking, a hot gas can develop between the brake pads and rotor and that the drilled holes and/or slots allow the gas to escape keeping this gas from interfering with the contact between the brake pads and rotors.

I had a car that I auto crossed. When I replaced the rotors I went with the same size but they were drilled. I did not notice any improvement in braking. I did notice that I started to develop cracks at the area of the drilled holes. I was told that the rotors were not manufactured poorly but that it was caused by the difference in temperature (expanding and contracting of the metal) at the area of the drilled holes. I have no experience with slotted rotors.

I put large Wilwood rotors on my Barracuda. I did not pay extra for drilled and slotted rotors. The car is mostly for the street and some occasional auto cross when I get it back on the road.

I do not believe the extra money is worth it for a street car. If it is a race car, it may be worth it to you.

Give a call to Wilwood, I gave had good experience with their tech guys. If you are racing auto cross or going to track days, talk to the other guys about their experiences.