Ok the overflow valve on the vp44. If I increase lift pump pressure to ~~18 psi wil I need to route a hose from the overflow to the tank. I am very confused on this people have all said no but then how does the fuel return to the tank if the overflow is opened?

 

the vp44 has a return line from the factory...fuel the vp44 does not send through the injection lines to be burnt, gets returned via the overflow valve into the return fuel line that dumps back into your fuel basket in the tank.

in the image below, the black line on the left is my factory vp44 return line.

the line hooked to the black QC fitting is the airdog return line, and the line on the far right hooked via the brass/aluminum JIC fittings is the suction/supply line.