I have a 600 CFM Brawler Carb similar to the Holley 4160 I replaced it with. The distributor vacuum advance is currently connected to the port on the metering block of the carb which according to the instructions is ported vacuum. There's another port at the base on the same side of the port I’m using. Is that ported vacuum as well because I don’t get vacuum from it unless the throttle is open, like the port I’m using on the metering block. The instructions show two ports there at the base and I only have one. I was also thinking of ditching the ported vacuum line to the advance in favor of manifold vacuum, which I'd have to get from the line currently connected to the PVC valve. BTW, the carb is on a 350 SBC crate engine, no special cam or heads, just HEI and long tube headers, it’s the base crate engine (we used to call them Target Master engines). Any help is appreciated.