Type of cooling vanes for ventilated rotors

Straight (non-curved) Vanes: (For general street brake applications)

1. Straight VanesStraight vane: This is the most popular, easy and straightforward vane type to make. Straight vane rotors are lighter and have better cooling capabilities than solid rotors. This is the design of most of the front rotors supplied by car manufacturers. Some higher-end models also use vaned rotors for the rear. The rear rotors are usually thinner than those in front.
2. Pillar VanesPillar vane: Instead of straight vanes, patterned random formations (dots or lines) are cast between the two friction plates. The Mistubishi EVO 8 front OE rotor is made with pillar vanes.
3. Variable vane: Similar idea to pillar vanes, but vary in different patterns such as Stoptech's™ patented Kangaroo Paw design.

All of these designs are non-directional, meaning both left and right rotors are constructed from the same casting. Do not confuse this "non-directional" (straight) vanes with the "directional" slotting or drilling. In other words, a pair of straight vane rotors can be machined to have directional slots or drillings.

  Non-directional Straight

For example a manufacturer can claim a "directional" (left/right) rotor based on its surface slotting or drilling, but the cooling vanes are straight, or "non-directional".

All of the above designs can save cost for the manufacturer, as they require only one set of tooling and are relatively easy to produce compared to curved-vane rotors. This also makes inventory control easier. Very few models are known to come with one-piece curved vane rotors. Some of these include the BMW M3, Corvette C6, and Toyota Supra Turbo. RacingBrake selectively upgrades per application list from OE straight vanes to curved vanes.

Curved Vanes: (Primarily for two-piece rotor construction, built for Motorsports tracking, and professional racing applications)

1. Traditional Curved VanesTraditional curved vane: This is the most commonly used design to improve the cooling effect by pumping the cool air from the center of wheel. Other manufacturers' two-piece surface mounted designs only allow cool air to enter from the inboard side of the vehicle. However, the air inlet is usually restricted by the dust shield, which essentially reduces the two-piece rotors' cooling effectiveness to the level of one-piece curved vane rotors. RB's center-mount design admits cooling air to enter from both the inboard and outboard sides.

The vanes also act as a heat exchanger to carry the heat away from the rotor.
2. Variable curved vane: An example of this is Stoptech's™ patented AeroRotor.
3. Convergent Curved Vanes Convergent vanes: This is RacingBrake's™ patented design. Convergent vanes are the most innovative design, and are paired with the latest production technology. Our design aims to further improve the cooling efficiency over traditional curved vanes.

  • The suction (air inlet) is wider allowing more air intake.
  • The discharge (air outlet) is narrower to increase air flow.
  • As the air pressure increases towards discharge, the air temperature also increases. The number of cooling vanes (which act as the heat sink / heat exchanger) also increases to handle the higher heat load.

Cooling Air RisesRB's exclusive design works out more effectively especially for curved vane because the nature of geometry. The outer circumference is larger than the inner circumference, this makes traditional curved vane design to have a wider outlet and narrower inlet which is in opposition to the need of heat removal from the disc and is one of the prime reasons of warping and cracking due to the uneven disc surface temperature.

Most of our competition has only one vane count (ie. 36, 42, 48, 52 or more). RB's™ products have variable vane count (inner-36, outer-54, total-72). We even vary the configuration of vanes. The vane count is not the only important factor; the design is also critical. RB's vane count and vane designs optimize the cooling effect and achieve an uniform disc temperature across the brake surface.