THE BEECHMONT CREST AUTOMOTIVE LEARNING ZONE
SUPERCHARGER / TURBOCHARGER
An engine normally uses atmospheric pressure to drive air into the engine. (At seal level, this is 14.7 PSI or 100 kPA.) An engine that relies on atmospheric pressure is called an atmospheric engine.
Since atmospheric pressure is inherently limited, there is also a limit to how much air and fuel can be driven into the combustion chambers and burned on each stroke.
Superchargers and turbochargers force more air and fuel into the combustion chambers, thereby increasing engine power beyond what can be achieved with atmospheric pressure alone.
A turbocharger is a blower or fan that is driven by exhaust power. A turbocharger not only increases engine power, but also improves engine efficiency by utilizing exhaust output. Turbochargers are used on small gasoline-driven engines. They are also common on diesel engines.
A supercharger is not powered by engine exhaust gases. A supercharger consists of chain- or belt-driven blower. Superchargers are more common on large racing and performance engines.