Electric fuel pump questions??

[Telecasterjoey]

Hey guys so I'm in the middle of my engine swap and now I'm at another road block. I need to use an electric fuel pump because the 1990 block I'm using doesn't have a casting for the mechanical (trust me I'd rather run one) After a search on here I still have a few questions.. To run my rochester q-jet I'll need around 5 psi correct? If I run an electric fuel pump do I need the return line?
How hard are they to wire up? And does anyone sell the entire kit with an oil pressure safety switch? How do you guys run your pumps?? Lots of questions I know!

Here are some pictures of the swap so far.
Pulled the van 350 first, pulled the truck 305 now I'm just cleaning and painting everything.

[Your41Plague12]

When my truck had an engine with the TBI block, we capped the return line and ran a pressure regulator for whatever carb I was running at the time. They're really easy to wire up. Wire it to where it has 12V when the key is on. If there is a way to keep it from coming on when the key is on ACC, do that (or just install a killswitch for whenever you need to use the electronics but don't want the fuel pump to run). Mine ran great, but prepare; if you mount yours on the frame rail, like I did, you will have the most annoying sound from the fuel pump echoing off the inside of your cab. It will drive you insane.

[East End K5]

not to hijack but how beneficial is running an electric fuel pump to a carbureted engine? Im a novice....lol.

[Your41Plague12]

Originally Posted by East End K5

not to hijack but how beneficial is running an electric fuel pump to a carbureted engine? Im a novice....lol.

If you have electrical issues like I did, it sucks. Plus the wires are exposed and can corrode, making the pump fail. I honestly prefer the mechanical pumps, that's why I got rid of the TBI block.

[notyo_cheez]

You need a 12V relay (to the control circuit side) tapped from the feed to your coil upstream from your fuel pump, this way the pump won't run when you have your key on ACC. Make a hot tap and dedicated fuse from your fuse panel for the power circuit for the fuel pump.

When you turn the key the 12V feed to your coil will energize the coil for the relay, closing the contacts on the relay and turning on the fuel pump. This is the correct way.

[Restrorob]

Originally Posted by Telecasterjoey

To run my rochester q-jet I'll need around 5 psi correct? If I run an electric fuel pump do I need the return line?

5 or 6 psi is fine, But it's always best to run a return line. This reduces back pressure which can reduce amp draw of the pump motor and the noisy cavitation associated with frame mounted pumps.

[raceman6135]

Originally Posted by Telecasterjoey

To run my rochester q-jet I'll need around 5 psi correct?

Correct. Anything from 5 to 7 PSI is acceptable.

Originally Posted by Telecasterjoey

If I run an electric fuel pump do I need the return line?

It depends upon the pump. Some require a return line, but most that are set up to run with carburetors at this pressure do not require a return line.

Originally Posted by Telecasterjoey

How hard are they to wire up?

Fairly easy. The pump needs to be grounded to a good chassis ground. The power wire can be run to an unused IGN terminal in the fuse block. IGN terminals in the fuse block will only supply power to the fuel pump when the key is in the "ON" position. As with any electrical connection, though, use a test light or meter to be sure. Also, remember to support the wire every 12 inches or so and keep it away from heat and moving parts.

Originally Posted by Telecasterjoey

And does anyone sell the entire kit with an oil pressure safety switch?

Not that I'm aware of.

Originally Posted by Telecasterjoey

How do you guys run your pumps??

Just the way I've described.

Don't forget that electric fuel pumps are not very good at pulling fuel; they are designed to push. Therefore, mount the pump as low and as far back (right beside the tank if possible) in the vehicle as possible.

Keep the amount of rubber hose you use to a minimum, and be sure to size all fittings, hoses and hose clamps properly.