I used 5/16” nylon for both supply and return (stock 5.0L).
I am also using stock foxbody fuel rails joining nylon in front of block in stock location to factory spring lock connectors.
All parts were sourced from Rock Auto.
Not all adapters are available or correct on Rock Auto according to product description.
So I I have a short piece of High pressure fuel injection rubber hose out of tank.
I am using Spectra 22 gallon FI tank for 70 Mustang.
I considered Tanks, but didn’t want fuel connections inside trunk.
Just make sure to put sealer on threads of your hardware for vapors and liquid.

AGS and S.U.R.&R. are the only nylon supply companies that were available when I performed my EFI conversion.

Again I used 5/16” for all nylon.
Used 3/8” FI rubber out of tank.
The quick disconnects work very nice too.

AGS FLNR525 = 5/16” Nylon (25’)..:.SUR&R has longer lengths available.
Hindsight should have just ordered a 50’ length.

AGS FLRQ040 = 5/16” steel to 5/16” Nylon straight fitting

S.U.R.&R. K310 = big spring lock

S.U.R.&R. K320 = small spring lock

AGS FLRL150 = 5/16” quick connect to nylon

Last edited by Nos681 (5/26/2021 8:16 AM)

  I have a Tanks Inc tank with the lines coming out the top of the tank from the pump.  I used  5/16 plastic fuel line from the vapor port to a 2000 Mustang charcoal canister in the engine compartment.  I have a 3/8 line from the tank to a filter in the RH muffler cavity underneath.  I have a 5/16 return line from the filter back to tank.  I have a Mastercool tool for making hose quick connects.  It will also push quick connects into the  plastic line.  I have roughly 6" plastic lines from the tank to the hard lines at the filter.  I have roughly 6" plastic lines at the filter then a 3/8 hard line from the filter that goes towards the engine compartment, converts to a 5/16 line and then connects to the factory braided line to the fuel rail.  This is with a 2000 Explorer 5.0 with "returnless" fuel using a 2000 Corvette filter with internal regulator.  I made a cover to go over the lines in the trunk to protect them.  My 3 lines from the pump go straight forward through the forward trunk floor through a big rubber grommet, then over the axle and head towards the right side muffler indention (I have Arvinode chambered exhaust).  The lines are held up by cushioned clamps to the floor.

When I had the 1988 Cougar 5.0 I had the same setup to the filter, but I had a return line from the fuel rail to where the filter is and joined that to the line to tank. The fuel lines both ran forward past the RH front wheel and used the Cougar lines to connect to the engine.  I had quick connects as needed to join the Cougar lines to the ones I made.

I strongly recommend using canister purge on any EFI conversion.  It keeps fuel smells to a minimum.

https://photos.app.goo.gl/YFgcZQgd6eFFK35U8
https://photos.app.goo.gl/xPEES9xbZe3Q9KA97
https://photos.app.goo.gl/jsW9MpGCPPy3hf6MA
https://photos.app.goo.gl/tbojesGgHCtvEVhX9
https://photos.app.goo.gl/9GH4GRzFobn8Jhmp6
https://photos.app.goo.gl/iewB6bxDpAJHEPRP8




 

Last edited by markdtn (5/26/2021 10:18 AM)

The last photo with the charcoal cannister was the original setup for an '88 Cougar 5.0 it was taken when I pulled that engine to put in the Explorer 5.0.  Where the vapor line comes through the apron the fuel lines  originally came there too.  I also added some spring wrap at that location so the vapor line didn't get a kink in it.  The vapor line is still there now but the fuel line comes up under the heater motor. (and did away with the starter solenoid since the later starter has a solenoid on it)

If you are going to make your own EFI hard lines I would look at a Mastercool tool.  It makes those lines so simple.  Also double flare brake lines are easy too.  Don't get to use it too often, but it is one of my favorite tools.

TimC wrote:

Thanks all for the ideas.  Yeah, it'll be steel lines as much as possible. The routing is complicated with everything we got going on underneath.  

  What EFI system are your running?