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Turbo system, overview

Turbo system, overview


Brief description

As distinct from a normally aspirated engine, the supercharged or turbocharged engine has better filling during the induction stroke, which results in more efficient combustion, increased output and higher torque. Engine performance is thus comparable to that of a bigger engine while retaining the advantages of the smaller engine such as fuel economy, size, weight, etc.

Supercharging

Supercharging is achieved by means of a turbocharger, which uses the engine exhaust gases as a propellant. The exhaust gases are directed through an exhaust turbine and start the turbine impeller rotating. The turbine impeller is mounted on the same shaft as a compressor impeller and rotates at the same speed. The compressor wheel is positioned in the induction system where it achieves an increase in pressure which results in improved filling of the combustion chamber.

The turbocharger is sized so that it starts to work at comparatively low engine speeds and therefore provides high torque in rpm ranges that are used during normal driving conditions.