My buddy is rebuilding a stang with a 351W it is carburated and we are wondering how to run the fuel lines exactly. How is the return line suposed to be run on an electric fuel pump. Is there a website that shows or anyone have any help on this.

 

There is no return line on a carbureted electric fuel pump. When the back pressure in the line to the carburetor reaches a certin level, the pump - stops.
Jim

 

You'll want a return style pressure regulator. I use a Holley unit. I also used my stock fuel line for the return, using a fitting into the gas tank. You can use a non-return style setup, but they are less efficient and can overheat the pump.

BTW, only the computerized fuel pump circuits will alter the pump's speed to change the delivery when the pressure is high. I'm not too sure if you want to spend the money for this kind of controller.

 

AFAIK, the pump's pressure (I'm speaking of the 6-8 psi models that do not require external regulators) is limited by mechanical means. As for overheating the pump, wouldn't Holley, et al, state this in their instructions and at least recommend a return line? There is nothing mentioned. I didn't think a return line was needed until you get to the higher pressure competition pumps with external regulators.

FWIW, my Holley red works fine without a return line.

To the O.P., is there any reason he doesn't want to run a mechanical pump? I had 400hp in a 351W with a Carter mechanical pump and never had a problem with fuel delivery. The only reason I'm using an electric now is because my Ford Racing crate motor did not come with a fuel eccentric and I didn't want to crack open a brand new engine to install it.

Good luck!
Jeff

[edit] I just re-read your post Colorado and it is clear to me that you are probably running a high performance high pressure pump with an external regulator. YMMV