Abstract: A vacuum control assembly for regulating the vacuum servo mechanism of an internal combustion engine's distributor including a vacuum sensitive device located between the carburetor spark and EGR vacuum ports and the distributor breaker plate servo mechanism, the device containing two parallel flow circuits connected to the servo, one being connected to the spark port and containing a servo operated cut-off valve, the other being connected to the EGR port and containing a servo operated switching valve that connects the distributor servo mechanism to the EGR port once the engine has reached a predetermined speed.