2000 explorer 5.0 swap- return less fuel system requirements

[Crazyhorse1977]

Good morning! I am swapping a 2000 Ford explorer motor and 4R70W tranny together into my 77, it has a returnless fuel system with it. I installed the Wild Horses M1A tank and plan on using a new spare aux tank for extra fuel to pump into my 23gal tank when needed. Do I need to install a specific fuel pressure regulator for my return less system? What exactly do I need to do?

 

[904Bronco]

Garry, EFI Guy, recommended this one to me.

https://www.summitracing.com/parts/aei-13129/overview

Aux tank, just set it up to pump into the rear main. (When the tank is near empty) (I think I used a Carter 4050 pump to do that)
Since you have a 77, the factory fuel caps venting, because of smog, may limit how fast you can move the fuel.

The regulator could be mounted on the frame in the back near the tank. Set it to the desired pressure and your good. But, you have to put it in a spot away from moving parts, exhaust, dirt, etc. You could mount it in the engine compartment and run an additional line back to the tank for the returned fuel. Hopefully, you have enough ports on you tank for all this...

 

[Oldtimer]

If it is a return LESS fuel system, why would it use a regulator with a return line to tank?

 

[Yeller]

If it is a return LESS fuel system, why would it use a regulator with a return line to tank?

It still has to have regulated fuel pressure of, I believe for a returnless 5.0, 68psi. The return line to the tank is from the regulator mounted near the fuel tank. Most of those systems from the factory run the pressure regulator inside the tank along with the pump so they only have the single line coming out to supply the engine.

maybe this will help.

 

[EFI Guy]

The returnless thing is just a myth. It just returned it before leaving the tank. See here...
https://classicbroncos.com/forums/threads/explorer-obd2-harness-re-work.257251/post-3021078

 

[EPB72]

There’s mechanical returnless regulator in tank part of fuel pump sender assembly,,,, or there is electronic returnless with fuel rail pressure sensor and fuel pump control module duty cycle to pump to control pressure…. But that’s on next gen explorers ..

 

[bronco italiano]

Garry, EFI Guy, recommended this one to me.

https://www.summitracing.com/parts/aei-13129/overview

Aux tank, just set it up to pump into the rear main. (When the tank is near empty) (I think I used a Carter 4050 pump to do that)
Since you have a 77, the factory fuel caps venting, because of smog, may limit how fast you can move the fuel.

The regulator could be mounted on the frame in the back near the tank. Set it to the desired pressure and your good. But, you have to put it in a spot away from moving parts, exhaust, dirt, etc. You could mount it in the engine compartment and run an additional line back to the tank for the returned fuel. Hopefully, you have enough ports on you tank for all this...

Yep, that is a good one.
I have a RobbMC version, probably made by aeromotive. https://www.robbmcperformance.com/products/regulator_fi.html

 

[Crazyhorse1977]

The returnless thing is just a myth. It just returned it before leaving the tank. See here...
https://classicbroncos.com/forums/threads/explorer-obd2-harness-re-work.257251/post-3021078

So since I have the wild horses efi 23 gal tank with in tank pump assembly I need to add a regulator at the frame or engine bay in line with a return line back to the tank? The tank has a return port. The feed and the vent. Do I tee the vent for the aux tank and the return from the reg? Sorry I’m new to this swap. Also I have one of your custom harnesses I had you do for me a couple of years ago.

 

[EFI Guy]

I would try to add the Explorer regulator into your tank just above the fuel pump. Just make sure any line you use in the tank is rated as submersible.
If you don't have enough room to fit the regulator in the tank then I would mount one on the frame rail and run the return back to the tank like Yellers diagram.

 

[widowmaker77]

I modified my 23 gallon tank to accept the oem explorer fuel pump assembly.

 

[samamarshall]

I’m working through this same swap and I’m on fuel lines now. Some people use this filter/regulator combo on frame by tank, then run single line up to engine

https://www.summitracing.com/parts/hly-162-590

 

[fordguy]

My tank was made to accept the factory fuel pump, so I just let the factory return less pump do its thing. Simple and clean.

 

[Yeller]

I’m working through this same swap and I’m on fuel lines now. Some people use this filter/regulator combo on frame by tank, then run single line up to engine

https://www.summitracing.com/parts/hly-162-590

This is the system I run. Now that the OEM application has not been in production for nearly 20 years and wasn’t a high volume unit any way, only C5 Corvettes, it has been found the quality of the regulators is hit or miss for the correct fuel pressure. In theory it’s not enough to be an issue, O2 sensors will keep the fuel ratio in check. I’ve personally not experienced any issues and have been running it since 2013, and have changed the filter a couple of times.

 

[EFI Guy]

The Vette filter regulates to 58 psi. The Explorer expects 60-65. Plenty of people run the Vette filter without issue. The fuel trims usually run around +5% with that setup, which is still within the computer's range of adjustment. Not the most ideal, but it seems to work ok.

 

[Yeller]

I should elaborate, I am not running an explorer or Ford engine