Why do some brakes have holes?

If you’ve ever been to a car show (or the parking lot of The Silver Saddle), you’ve probably noticed that certain ultra high-end cars have massive brakes with holes like Swiss cheese. How come?

These are called “drilled rotors,” and the idea is that the holes allow heat, water and brake dust to escape more easily. This gives the caliper a cleaner surface to bite onto, improving braking and stopping performance.

The drawback is drilled rotors can’t be resurfaced, meaning you have to replace them twice as often. But I imagine that most McLaren, Lamborghini and Mercedes-AMG owners don’t mind.

– Chris Butsch, The Arizona 100