3. Mechanical Efficiency. The mechanical efficiency referred to maximum load is increased
since the increase of frictional losses with a supercharger driven directly from the engine is quite smaller
as compared to the power gained by supercharging.
4. Fuel Knock. It is decreased due to increased compression pressure because increasing the
inlet pressure decreases the ignition lag and this reduces the rate of pressure rise in the cylinder resulting
in increasing smoothness of operation.
5. Volumetric Efficiency. Volumetric efficiency is increased since the clearance gases are compressed
by the induced charge that is at a higher pressure than the exhaust pressure.