[HILLY]

Bill,

It would be interesting to know what the ‘ideal’ prescribed vacuum is and what is actually achieved via the manifold connection as in Jerry’s set-up.
I assume that the vacuum pump / relief valve set-up will provide a constant crankcase vacuum regardless of the operating conditions where as the manifold connection will have a fluctuating vacuum throughout the RPM range.
Although there is not a huge gain, Jerry’s set-up is virtually cost free and every little bit helps and all adds up in the end.