DATSUN 1970-72 240Z Engine Modification: Description

Engine modification system consists of a vacuum control valve which detects intake manifold vacuum. Valve operates a servo diaphragm which controls the carburetor throttle valve. System is activated during periods of deceleration. An altitude compensation device is contained in system. This device compensates for variations in altitude so that valve can function properly at any altitude. Automatic transmission cars also utilize a dual point distributor which provides for both advanced and retarded spark timing under various conditions.