Forced induction

Forced induction is a term used to describe internal combustion engines that are not naturally aspirated. Instead, a gas compressor is added to the air intake, which increases the quantity of air or fuel-air mixture that is available for combustion.

Forced induction can be used to improve the power output of an engine, its efficiency, or both, without much extra weight. Pressurising the intake of combustion ingredients increases the effective capacity of the engine without an increase in physical size. The forced induction approach has the advantage that the intake pressure may be related to the engine speed, providing power from extra capacity at high speed, but not wasting fuel at lower speeds.

The two different forced induction technologies in common use are superchargers and turbochargers. They differ mainly in the power source for the compressor.

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