Switching to an electric fuel pump on my 78 f150 400m auto trans 4x4 and need to know what gph and psi rating i should run the motor is stock and i just put a newly remand 2 barrel autolite carb on it also would i need an fpr and where could i get an electric pump for a reasonable price. thanks


Asked by Apr 10, 2013 at 03:15 AM

Question type: Maintenance & Repair

4 Answers

http://www.summitracing.com/search/department/air-fuel-delivery/section/fuel-pumps-regulators/make/ford/part-type/fuel-pumps-electric-external is a good pace to start...... then http://www.onlyfuelpumps.com/ ...also has a good selection, you are going to need a cover plate for the hole where the old mechanical fuel pump 'used to be" don't leave it there. Now gph is gallons per hour I am guessing? I have no clue. But it does not matter really, the electric pump will provide more than enough for that 2bbl. Now..gravity feed for most engines is about 1 to 2 psi, and an electric one will give you as much as 6psi more than enough, Too much even. The mechanical pump provided about 3psi It does not need much as far as pressure is concerned. Buy a pump that is adjustable, i.e. you can set it at what pressure you want it to kick on and off and set it at 2.5psi. If the 'settable' pumps are too expensive or not available make sure it kicks off at 3psi ...or LESS Anything more than 3 or 3.5 is too much for the float. Put at least 2 in~line fuses on the feed wire, one right at the power source, a good place to run your wire from is the starter solenoid, where the short red cable from the battery goes, hook up a fuse, then a 16g wire will do, run your wire to wherever you decide to put the pump. It has the gas tank in the cab behind the seat..right? I put one on my '78 under the side panel just behind the driver door. I chose that place because it's easy to get to, and easy to run wires and fuel lines to it, it's gonna get mud caked real fast. Put another fuse right before where you pass the wire through. Ground the pump near its self right to the body. Run your fuel lines from the tank through the same hole as the wire, and to engine the same way.

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Just a couple questions for you if you don't mind. What is 'fpr'? What are you asking on that? And what does 400m mean? In 1978 there was a 6.6L, 400 cubic inch engine available, that was a redesigned 351cid Cleveland. Is that what you mean? Thanks brlange


FPR = fuel pressure regulator. I don't know what "400M" is either. It could be a engine or transmission by it's context. Two fuses is unnecessary but if you do want to double up, put a larger fuse near the source of power and a lower numbered fuse near the load. That's called selective tripping in the electrical world. It will also tell you if the the load drew too much power or if you had a short circuit to ground in the line.

Point taken. thanks man. Good morning to ya and everybody!

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