Brake rotor cooling vanes — Why they’re important

Vented brake rotor cooling vanes dissipate heat and help you stop faster

When you apply the brakes, all forward motion is converted into heat right at the brake pad and rotor. In most cases, 80% of the heat is absorbed by the rotor, with the rest in the brake pad friction material, backing plate and caliper. To cool the rotor, carmaker Porsche invented the internally vented brake rotor in 1965. Unlike the previous solid rotors, the internally vented units are cast with cooling vanes that act like fan blades to move air between the two rotor discs. The vanes draw air from the center of the disc and move it between the two disc to pick up heat and exhaust to the outer circumference. The straight brake rotor cooling vanes shown below are the least costly to manufacture, but they also create the least amount of air movement.

So carmakers have developed other vane configurations to increase airflow and improve braking, like the curved vane and pillar vanes shown below. If your vehicle came equipped with curved or pillar rotors or any other variation, it’s critical that you replace them with the exact same cooling vane configuration. That’s the only way you can obtain the same braking.

Straight vanes

The simplest rotor vane design is straight vanes. They cost the least to manufacturer but are the least efficient for cooling the rotor.

Curved vanes

Curved vanes tend to scoop more air than straight vanes. They also keep the air inside longer to remove more heat.

Pillar rotor cooling vanes

A pillar design forces the air through a maze-like patterns of tear-drop or diamond shaped pillars. That creates air circulation within the ventilation chamber. This design removes the most heat, but is the most costly to manufacture

Brake manufacturer Brembo patented the the pillar style cooling vane shown on the right. It’s referred to as Pillar Venting Technology (PVT)

©, 2022 Rick Muscoplat