racersedge1821

ok guys me again back to the project whats up is i just swapped my 383 carbed into my 91 rs was 305tbi what i want to know is do i need to do anything to make my in tank pump work properly i already put the oil pressure sending unit in to activate the pump just was wondering if i needed to do anything else to make it work reiably ty

vetteoz

iTrader: (13)

You don't even need the OP switch although handy as a backup as in factory setup .
Just run a "hot when key on" wire to the fuel pump relay; pump runs as soon as key turned on

camaronewbie

I took my oil pressure sending unit out of the fuel pump equation. I found out the hard way that the OPSU can go bad and 'think' it's getting oil pressure when it's not (ie car off key in pocket) and it can make the fuel pump run constantly until the battery is dead (since it has a direct connection to battery). So I rewire my OEM relay using the wires from the OPSU and a hot-in-run, so that when key is on, relay is energized and the OPSU fuel pump wires get connected to one another, making the pump run - but ONLY when the key is on.