Fuel system info

I also use the Corvette filter/reg on my 65 Dart (see post). I have found 4 basic types of EFI external pumps.

Ford 80-90's V-8 truck type is cheapest ($50), since often from China. It has a big threaded plastic inlet like in-tank pumps. A brass hose fitting screws onto the inlet, but I recall seeing that fitting only for 5/16" hose.

Walbro pumps come in several volume flows and sold under many brand names. Can buy new for $100 on ebay or get a used one from a tuner who thinks he needs more flow. More capacity than needed will uselessly heat the fuel. If running TBI injectors (~20 psi), the pump's volume capacity is much more than at MPFI pressures (55 psi), so no sense buying big for that. Can get fittings for 3/8" hose barb inlet & outlet.

Holley gear-rotor pump that came with their Pro-jection system. Slightly smaller than all above, funky electrical connector so get that with a used one. Even Holley changed to above pumps. I used one for over a decade. Initially failed 1 or 2, but my fault (restricted inlet). It was mounted in the rear of my Newport.

Bosch Jetronic pump, used on Euro cars (M-B, BMW). Fatter than all above and seems more rugged. Marketed under various names as a high HP upgrade. I use one on my Newport now because I found two new ones for $15 on ebay. Most have a special banjo outlet fitting w/ check valve, but you can find a few adapters. Only place I found the mating banjo fitting was a DeLorean website (John used that pump).

EFI hose is very expensive ($5/ft?) so minimize use. Steel tubing is lighter and cheaper. New cars use nylon tubing but quite expensive, tricky to use (heat & wiggle on, no hose clamp and amazingly it doesn't blow off the fitting). It can crack as it ages. Very light and fairly stiff, so need fewer supports.

My sender is 3/8" outlet w/ 1/4" return (vent). I see 10 psig return pressure, which actually works good when I substitute a carburetor, w/ in-line reg to drop to 5 psig. However, Holley says to keep return <4 psig. I can't imagine why that matters since the injectors don't see that pressure.

I am probably the only one who mounts the EFI pump in the engine bay (lower frame rail). Works fine for me. Holley and others say "must be close to tank and below fuel level". I am a mech engineer and my last job was at Crane Valve, so allowed to think for myself. One advantage of a rear pump is you can use a shorter return tube and run just one tube forward, assuming your reg is back there. Cars since ~2000 have done that - federal mandate of "return-less" fuel system. It is a nasty place for a pump and tougher for roadside repairs, plus can transmit noise into the cabin, but put it there if it comforts you.