The purpose of the supercharger is to increase the compression ratio of the air before it enters the engine for combustion. In a supercharger, the compressor used to increase this ratio, is driven by the engine itself, thus decreasing the overall efficiency, for the same fuel consumption levels, as compared to a turbocharger. Its output is however steady and can be significantly increased by increasing the fuel consumption.
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A turbocharger is a device which used the exhaust gases to drive a compressor and help the engine produce more power from the same displacement. The operation of the turbocharger depends on the pressure and temperature of the exhaust gases. These gases operate a compressor which increases the pressure of the air about to enter the engine, thus increasing the efficiency.
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