Stock Racing Cars
To achieve this level of speed and control, stock cars are precisely engineered: the engine, the suspension, and the aerodynamic body design enable these cars to obtain such incredible speeds.
The critical part of a stock car is its engine. Although the shape of a stock car’s body is designed to look like a domestic sedan, the stock car’s engine is an unruly beast. The size of a stock car engine is around 358 cubic-inches (5.87 liters), which puts out around 750 horse-power! This massive amount of power comes from the highly tuned fuel system, which can deliver a huge volume of gasoline and air into the engine. The exhaust system is also highly tuned and efficient. In fact, a stock car engine is so powerful, in some race-circuits the engine must be fitted with a restrictor plate, which lowers the power of the engine for safety reasons.
The suspension of a stock car is perhaps the most precisely tuned aspect of the entire vehicle. It has to be—the suspension keeps the driver in control of the car, and a loss of control can be disastrous. The most important parts of a stock car’s suspension are its shock absorbers and its sway bar, both of which keep the car under control while the driver performs surgical maneuvers at high speeds.
The stock car’s body also helps to increase its performance. It does this by creating what is called down-force. The body panels of the stock car, along with the rear spoiler, cause the air flowing past the car to point toward, providing greater traction for the car’s tires—greater traction translates into greater speed.