super charger
When it comes to squeezing more horsepower out of a given number of cubic inches, nothing beats a blower (except maybe a turbocharger, which is the rival form of forced induction). The amount of power any engine produces depends on how much air/fuel mixture is pumped through it in a given instant of time. To increase the engine's power output, therefore, you either have to increase the engine's displacement (more cubic inches), increase rpm or increase breathing efficiency (called "volumetric" efficiency)..
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