car is being raced, how many laps are being run, track conditions due to weather, and how many caution runs require more braking. There are three variables to consider in racing: brake pedal displacement, brake pedal force, and vehicle deceleration. Various combinations of these variables work together to determine the stiffness, sensitivity, and pedal force of the brakes. When using the brakes effectively, the driver must go through a buildup phase and end with a modulating phase. These phases include attaining maximum deceleration and modulating the brake pressure. Brake performance is measured in bite and consistency. Bite happens when the driver first applies the brakes and they have not warmed up to the correct temperature to operate efficiently. Consistency is measured in how consistent the friction is during the entire time of braking. These two measurements determine the wear of the brakes. Engine The race car's engine needs a considerable amount of air to produce maximum power. The air intake manifold sucks the air from scoops on the hood and front bumper and feeds it into the engine. Many engine modifications to increase horsepower and efficiency are commonly used in many racing-sanctioning bodies. Engines are tuned on a machine called a dynamometer, which is commonly known in the racing world as a DYNO. The car is driven onto the DYNO and many gauges and sensors are hooked up to the car that are controlled by an online program to test force, torque, or power. Through the testing, the car's engine maps can be changed to get the most horsepower and ultimately speed out of the vehicle. Racing driver Racing drivers, at the highest levels, are usually paid by the team, or by sponsors, and can command very substantial salaries. Contrary to what may be popularly assumed, racing drivers as a group do not have unusually better reflexes or peripheral response time. During repeated physiological (and psychological) evaluations of professional racing drivers, the two characteristics that stand out are racers' near-obsessive need to control their surroundings (the psychological aspect), and an unusual ability to process fast-moving information (physiological). In this, researchers have noted a strong correlation between racers' psychological profiles and those of fighter pilots. In tests comparing racers to members of the general public, the greater the complexity of the information processing matrix, the greater the speed gap between racers and the public. Due partly to the performance capabilities of