By using dual active ventilation, the cooling capability and judder resistance improves significantly compared to the standard ventilated disc.
For standard ventilated disc, the cooling air flows from the inside of the brake hat. The DAV disc has a superior structure which takes in the air flows from both inside and outside of the brake hat. The result is significantly better cooling performance. Moreover, the heat build-up which leads to brake judder can be prevented by proper cooling. When the DAV disc is compared to a standard ventilated disc, the DAV has higher disc resistance from thermal cracking, which helps prevent brake judder.
Cooling air flows from the inside of the brake hat.
Cooling air flows from both inside and outside of the brake hat.
The deformation amount of the disc is proportional to the ratio of the width of the friction surface of the disc (A) and with the diameter of the hat of the disc (B).
On a standard ventilated disc, the hat (B) has a smaller diameter compared to the width of the friction surface (A). When deformation occurs from heat, there is a bigger impact on the outer edge of the disc. On the other hand, the DAV disc has a smaller width on the friction surface (A) with a bigger hat diameter (B). The impact of the deformation at the outer edge of the DAV disc is comparatively smaller than that of standard ventilated disc. The braking surface is sloped in the opposite direction compared to the OEM, therefore there is minimum effect on the braking feel.
standard SD rotor | DAV SD rotor | |
---|---|---|
temperature of rotor | 553°C→396°C | 542°C→368°C |
temperature of caliper | 185°C→164°C | 163°C→144°C |
This test was carried out using a Subaru BE5 Legacy on a closed test course. The DAV disc was fitted on the right axle and the standard ventilated disc was fitted on the left axle.