Turbocharger - Gasoline: Operation: Notes
Air is drawn through an air inlet duct and throttle body, into the compressor, then forced into the intake manifold, where the fuel is injected. As engine load increases and throttle is opened, more air/fuel mixture flows into the combustion chambers. As this mixture is burned, a greater volume of hot exhaust gas enters exhaust system. This gas is directed into turbocharger turbine housing.
Some energy contained in exhaust gas is used to increase speed of turbine wheel. The turbine wheel is connected by a shaft to compressor wheel. As the compressor wheel spins faster, it compresses incoming air and forces a denser air/fuel mixture into the combustion chambers. Higher engine power output is the result.