<P> A supercharger is an air compressor that increases the pressure or density of air supplied to an internal combustion engine . This gives each intake cycle of the engine more oxygen, letting it burn more fuel and do more work, thus increasing power . </P> <P> Power for the supercharger can be provided mechanically by means of a belt, gear, shaft, or chain connected to the engine's crankshaft . </P> <P> Common usage restricts the term supercharger to mechanically driven units; when power is instead provided by a turbine powered by exhaust gas, a supercharger is known as a turbocharger or just a turbo - or in the past a turbosupercharger . </P> <P> In 1848 or 1849, G. Jones of Birmingham, England brought out a Roots - style compressor . </P>

What do the numbers on a supercharger mean