The regulator is not independant, it is a "saucer" type regulator that snaps onto the fuel pump canister top. The inlet hose, which is part of the canister top, is actually inbetween 5/16 and 3/8.
I'm asking about the inlet to the regulator from the pump inside the pump basket. Yes you would of had to take one apart to measure it. Basically what I'm asking is for the smallest dia restriction in the fuel system. I'd like to use the viper truck pump in a ram if it will offer more volume at pressure. There are several rams dropping pressure at WOT.
That is exactly what I am talking about. There is a nipple on the INSIDE as well, the inlet from the fuel pump itself, attached to the underside of the canister top. Specifically, it is part of the regulator assembly.
Ok,, I have viper truck basket & pump. Now I see what I wanted. I'm going to test this in a turbo'd truck. Thanks