Disc brakes and drum brakes have different structures:
Disc brake disc brake braking force than hub brake braking power is small; Drum brake hub type braking power is large; You can see all the big trucks and engineering cars; Why do most cars use disc brakes? It is mainly due to the good heat dissipation performance of the disc type and the thermal decay performance of the braking force. That is, his braking force must be stable. Floating within a small range, even when it is hot, and the defect of hub-type braking is that the thermal decay is not good, and the thermal braking power changes greatly, and the recession is almost non-existent.
Therefore, for high stability, most high-speed cars use disc type.