I wasn't sure where to post this but since I have an lt1 I guess I'll try here. I'm looking at various inline fuel pumps to power my car (my lt1 is in a 69 that I can't put a pump in the tank so I have to use an inline). I currently have a 163lph inline on now but I want to upgrade. I was looking at the vortech ones. The smaller one is rated at 247lph @70psi. My question is when comparing it with a 255lph rated somewhere in the 30psi range which one flows more? I was thinking the vortech flows more since it's rated at 70psi and the regulator is really just a restriction...Is this right? Thanks!

 

You need the flow rating for each pump at the operating pressure of your fuel system. With the LT1, you're operating as 43.5psi, as long as you haven't installed an adjustable fuel pressure regulator. I run a Bosch pump rated 205 lph at 45psi, and its good for 500HP. I have a second matching pump for nitrous, and running a 300-shot with it.

A safe way to size the fuel pump, at least for an engine without nitrous or a blower, is to multiply flywheel HP X 0.45 to get the required liters/hour.

You are directionally correct in your thinking on the 247@70psi being capable of higher flow than a 255@30psi pump, although to state that with absolute certainty, you would have to look at the actual curve of flow vs. psi for each pump. But its likely that the 247lph pump will flow more.

 

Alright thanks fred!