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The bypass is operated by a vacuum actuator control unit that is normally closed. When vacuum is high the actuator opens the bypass valve, equalizing the vacuum pressure throughout the system. When boost is required the vacuum is decreased and the bypass valve closes, causing pressure to increase into the cylinders. This equalized vacuum condition virtually eliminates the normal parasitic power loss of a forced induction system.
Whipple Superchargers standard bypass was designed for those applications where space limitations or plenum/manifold shape or other considerations dictate a remote bypass. The four bolt flange should be mounted on the inlet tube or casting and the 1 1/2 inch tube should be plumbed to the discharge side of the supercharger.
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