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Manifold vacuum - Wikipedia, the free encyclopedia
What kind of pump is better - belt driven or electric?
Depends on what you are using it for. For brakes electric, to apply a vacuum to the crank case belt driven.
A vacuum pump on the crank case removes the air spring in the motor and tightens piston ring seal while helping reduce/eliminate blow by. The amount of vacuum you would want to run is around 10-15"Hg