So I've collected most of the underhood parts I need to convert the F250 (along with the new 351 going in it) to EFI, now I'm trying to map out the fuel lines. I'm hoping I can plunder everything I need off an '86, but trying to think ahead here.

I've got new sending units/pumps from an '86 F150 5.0 EFI, but still need the hi-pressure pump from the frame rail and tank selector. Hoping to harvest those this weekend. I've got a line on an unmolested 86 F150 being parted, but not confirmed if it's dual tank yet.

Is there one particular tank selector I'll need? Does it matter as long as it's off an EFI truck? I assume 85-86 would be basically plug-and-play for my application? LMC shows a lot of different ones and I'd like to keep it simple.

I'm not worried about the line behind the frame-mounted pump, but obviously the line in front of the pump has to support ~50psi of fuel pressure. Again, the plan here is to yank everything off the '86, but just in case it doesn't work out...

I've found some barbed spring lock connectors on-line (does the '86 fuel rail use spring locks? The one I've got is off an 96 E150...), so fabbing up lines from nylon line seems like an easy solution - provided nylon line and barbs will stand up to the pressure. Any worries with 5/16" nylon line from the pump to the filter to the rail?

 

The fuel selector valve on the 85-86 can cause problems.
If I was doing it I would get all the fuel lines pumps and tanks off of a 1990-1995 truck.
It would be much more reliable and I think you would have less problems.
Then you would not need the high pressure pump on the frame.

1985-1989 set up:


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1990-1996 set up:


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That was my first thought as well, but I hear tell the gas gauge won't work correctly with the newer model sending units. Plus I've already spent ~$400 getting the fuel tanks reconditioned.

 

I have heard that also but I just checked all the 1988-1995 wiring prints for the F-series and all of the fuel tank senders are 145 ohms full and 22.5 ohms empty and are wired the same at the tank.
They may be different in trucks older than 1988 as I do not have that information at hand right now but will look it up later.

 

Thanks, I appreciate the info. All this EFI stuff is tough on an old carb guy. Hopefully the adage about old dogs doesn't apply here.