Does downforce affect braking

Answer 1

Yes, downforce aids in vehicle braking by providing more normal load to the tires without additional mass that needs to be accelerated (braking being acceleration in the negative longitudinal direction). This additional normal load allows a larger braking torque to be applied by the braking system without locking the tires. In many race cars, the driver has to apply successively less pressure on the brake pedal as the car slows down not to lock the tires. This is a result of less downforce (and therefore less normal load on the tires) as speed decreases (note that downforce scales with the square of speed, so 1/4 speed means 1/16 downforce). Another benefit of aerodynamics packages in braking comes from the drag that is created, which also helps to slow the car. Open wheeled race cars create enough drag at top speed to brake at 1G by just letting off the gas pedal. Total braking acceleration can be as high as 5.5G for this type of vehicle, mainly due to the effects of downforce and drag.