What is Supercharging?

If you are a fan of loud sports cars with top-of-the-line horsepower, then you are probably a fan of supercharging. The concept of finding inventive ways to increase engine power has sparked car enthusiasts' interest for decades, and is not letting up: Superchargers are finding their way into ever-increasing numbers of cars worldwide.

The Facts

The supercharger is an air compressor that forces induction (or mechanically blows air) of an internal combustion engine. They are mainly made for sports and drag-racing cars or trucks.

History

Supercharging has been around for over a century and is about as old as the internal combustion engine. Gottlieb Daimler, a German automotive pioneer, became the first person to patent a forced-induction system for internal combustion engines in 1900. Automotive brands such as Auburn, Cord, Duesenberg, Stutz, Mercedes-Benz and Packard use supercharged engines during the 1920s and '30s. Even the British used supercharging to shoot German Zeppelins during World War I. In 1938, General Motors' Detroit Diesel Division gave supercharging a boost when they created the 6-71 supercharger. It was made for heavy-duty diesel engines. The GM 6-71 is still used today.

Function

Supercharging gives an instant throttle response and a powerful boost at low engine speeds. Once the throttle is open, the supercharger delivers the boost of speed instantaneously. This happens because it is belt driven off the crankshaft. Since the blower speed is proportional to the engine speed, the boost increases at the same rate as the engine speed, developing some serious horsepower.

Types

The two basic types of superchargers, when looking at the method of compressing, are positive-displacement and dynamic compressors. The positive-displacement pumps will deliver a fixed amount of volume of air per revolution, no matter what the speed is, while dynamic compressors accelerate the air to a high speed and then exchange that velocity for pressure by slowing it down.

Warning

Anytime you use a supercharger, be aware of the compression. With all the extra air from the blower and the amount of fuel that flows through the cylinders, detonation (engine damage) could occur if the compression goes haywire.