"No other device since the shields and lances of the ancient knights fulfills a man's ego like [a car]."
Sir William Rootes, automobile manufacturer
Superchargers, also called blowers, are used in cars to increase the power of internal combustion engines. German automobile-maker Gottlieb Daimler (1834-1900) first came up with the idea of pumping extra air into the engine to increase the horsepower. This effectively makes an engine larger for less weight, which is ideal for racing cars and aircraft. Initially engines relied on atmospheric pressure to keep air inside the engine. By pumping extra air into the engine, the amount of oxygen was increased, and this burned more fuel, giving the vehicle a power boost.
Daimler's design was based on twin-rotor air pumps that forced extra air into the system. His design went into production in Mercedes and Bentley cars in the 1920s and was essential to World War II aircraft. Today, superchargers are defined as any gas compressor driven directly by the engine. The supercharger's more powerful rival, the turbocharger, uses the exhaust gases to drive a turbine to blow in clean air. Both designs are essential in airplanes, since they experience a loss in atmospheric pressure as they climb to higher altitudes. At 18,000 feet (5,500 m) the air is at half the pressure of sea level, and hence twice as much air has to be blown in to keep a constant power.
The complexity and price of superchargers have restricted them to the more expensive cars on the market. Adding one to your current set of wheels will provide more horsepower per pound than any other component, perhaps bar the turbocharger.
