Differential Valve Delay Valve (DVDV)

This delay valve is used to delay air bypass during periods of low engine manifold vacuum. The DVDV is installed in series with the vacuum differential valve (VDV).

This installation of a delay valve in the sense vacuum line delays operation of the vacuum differential valve during sudden drops in manifold vacuum such as during hard acceleration. During sudden deceleration, the sudden rise in intake manifold vacuum opens the check valve in the delay valve, passing the signal along instantly.