I’m in the process of converting my 1978 F-250 to fuel injection, and I had a question about fuel pumps. Several people I’ve spoken with tell me I should do whatever I need to do in order to have the fuel pump in the tank. This is kind of a big pain. It would be really easy to just add an external high-pressure pump and mount it on the framerail, not to mention much easier to access should the pump go bad. I understand there are very specific mounting requirements for an external pump, but I already have a great spot to put one that meets all of them. Are internal pumps really that much better? How am I supposed to add a pump to a tank that isn’t designed for one?
It’s hard to deny the benefits of fuel injection these days, especially for off-road use. Retrofitting a fuel-injection system is easier than ever thanks to the variety of good aftermarket systems on the market, and because of this, more and more fuel pump solutions are available all the time.
You are absolutely correct. Most of the time adding an external pump to a fuel system that originally fed a carburetor is much easier than going with an internal pump. That said, we would still recommend going with an internal pump if possible. Although it’s a lot more work up front and harder to access for service, the main advantage to an internal pump is cooling. Because the pump is immersed in gas, the pump stays cool and lasts much longer. The biggest enemy of anything electrical is heat and moisture, and external pumps are subjected to a lot of both. Mostly for this reason, it has been our experience that nine times out of 10, an internal pump is going to be more reliable and is therefore worth the extra installation hassle.
Your internal pump options include using a bed-mounted fuel cell, retrofitting a later-model EFI tank to your truck, or retrofitting a pump to your existing tank. There are different costs and installation difficulties associated with each one, but retrofitting a pump to your existing tank is easier than ever with Aeromotive’s Phantom fuel systems (aeromotiveinc.com). The system is pretty slick and offers a comprehensive, easy way to add an in-tank pump. You cut a hole in the top of your tank, and the kit includes everything you need to install, secure, and seal an in-tank pump. The Phantom kits are available as both return and returnless systems to match whatever fuel injection system you use.
If you still decide to go with an external pump, we would recommend using a common one and carrying a spare. We’ve had varying degrees of success using a Ford E2000 pump. For whatever reason, some of our vehicles have done well with an E2000 and others have not. An E2000 pump puts out about 80 psi, so it will need to be regulated for most EFI systems and it will also need a return line. Mount the pump as close to and even with the bottom of the tank as possible, and buy the highest-quality pump you can find. Aeromotive offers some external brushless fuel pumps that we’ve heard good things about as well, but those aren’t available at your local parts store if one happens to go bad.
One last option is to use the existing mechanical low-pressure fuel system to feed an underhood sump containing a high-pressure pump that in turn feeds the EFI, such as what is offered by Edelbrock (edelbrock.com). Some people feel the system is overly complicated because you’re relying on both a mechanical and electric pump, but this option is the least invasive if remaining close to stock as possible or going back to a carburetor is a priority. The sump takes up some room, but with the cavernous engine compartment on your F-250 it shouldn’t be a problem finding a place to mount it.