ok, i have a holley 600VS on my 350 and i have a electric fuel pump, but want to get a mechanical one because i want more reliability, plus it looks crappy. If i buy like a holley street pump that bolts to the block, would i need a fuel pressure regulator??? and what about in tank pumps, what are they and when would i need to upgrade???

 

if you leave the in tank pump, it will supply enough fuel for you. you do need to regulate it between 5-7 1/2 psi. if you decide to go with the manuel pump, disconect the electric. the gas will pull through it. here's a pic of my regulater