I am looking into a Holley Sniper Fuel injection Kit for this 460. How does the return line work using dual tanks? Is there a clean way to use the existing switch to pull and return from either tank? Do I need 2 separate pumps, seperate switches?
Thanks!

 

Once you get pas the FiTech part and check out this guys return line set up. At least to ONE tank. https://www.ford-trucks.com/forums/1...n-77-f150.html

Walbro GSL392 pump, WAY quieter that most elec fuel pumps. Not sure on the rest of your questions.

EFI inline filter idea. https://www.ford-trucks.com/forums/1...injection.html

 

I'm trying to think this out in my head.

I put a Holley Sniper on my 78 Bronco. It only has one tank of course. I used their master kit and ran the supplied fuel hose as my delivery line to the Sniper and then used the existing steel hardlne that used to feed my mechanical fuel pump as my return back to the tank.

I haven't looked at the dual tank setups. I have an F150 that has it, but I haven't had to mess with the fuel system on it to know everything there is to know. However! If I was trying to mimic what I did on my Bronco and had two tanks, I'd source a second OEM valve/solenoid that these trucks use when you flip the switch on the dash to change tanks and I'd wire them together to switch together. Then I'd run my return from the sniper to one valve/solenoid and have it split off to each tank, so it'd return to the tank I was pulling from and then use the other for the delivery line like it already does from the factory if all that makes sense. Again, I'm just kinda thinkin' out loud here.

You could just have one return to your main tank, but then if you were using the aux tank you'd be slowly filling the main tank back up via the return if that matters to you. Holley wants the pump as close to the tank as possible, so that would be something to work around as well as it having to be between the dual tank valve and the Sniper for it to work as I just described earlier.

Just food for thought. I'll keep thinking about it and see what my mind comes up with.

 

I JUST saw this done a couple days ago, but it was on a Cummins conversion with a mech. pump on the block. He used a second factory valve, plumbed up the same way and triggered with a jumper wire from the original. Appears to work just fine. He made little pipe spacers and longer bolts, mounted it right on top of the existing one. He ran the tank return lines up and stuck a fitting in the vent line for the time being, but said he was planning to add a drop tube inside when he drops the tanks later on. He was worried about foam, with gas you might be fine just like that.... I’d considered doing that a while back when I was planning out a similar setup to what you’re doing, but this was the first operational one I’d seen running like that.

As far as pumps, one thing I’ve done on old 2Ton trucks with saddle tanks is run 2 pumps and just tee them together, no valve at all, figuring you can’t force fuel back through the check valves of the non-running pump. On a dent, you could use a no/nc dual pole relay (most average fog lamp relays are like that), have the nc pole feed the main, the no pole feed the aux, and trigger it with the existing valve wire - then use the existing valve replumbed for the return. I did them that way on the trucks to eliminate both the manual valve on the floor and the mechanical pump, I can’t seem to source either one that will hold up to “new” gas. That would be an option for what you’re doing, you’d need 2 pumps, though -

On edit - ack, 77&79 linked to the exact thread I was discussing it last year (and still haven’t done, gotta love projects)!! But yeah, same-same.

 

Thanks for the replies! Any idea how much these pumps are actually returning? I'm wondering about just having it return to the main tank, of course this would be funky using the AUX tank as my fuel gauge would really be dropping!
Not ideal. I hate to complicate such a simple system, but I guess that's what you're doing with EFI anyway

 

I remember the instructions saying somthing about the return line returning at a specific psi range. It was single digit, I know that. As far as volume, no idea. I could pull off my return under the hood and stick it in a jug and prime the pump a few times by cycling the key and see what comes out. Or turn on the engine and see how that goes. Lol

 

I installed a Holley Sniper on my 460 with dual tanks, and I put a Tanks Inc pump in a 38 gal tank with return. On my midship tank, I installed a simple electric inline fuel pump and one-way flow check valve plumbed solely to my rear tank by way of the existing ports on the fuel senders. Power to that pump is supplied using a momentary rocker switch. The mid-ship tank acts as a reserve supply to the rear tank giving me a 57 gallon range. Works great, although, with my 38 gallon tank, it is totally unnecessary. I just did it to see if it could be done.

David

 

I have a Fitech and dual tanks in my Supercab. My 460 has a little to much compression for towing so it pings a lot when pulling a load. I wanted to have 93 in the side tank and 87 in the rear.
I have an external Walboro pump for each tank, a three way switch turns on the pump I want o use. The factory selector switch controls which tank the gauge reads. The return line branches off to a shutoff valve that I have behind each fuel door. Open the valve for the side tank and close the valve for the rear tank and the fuel dumps into the side tank. Previously I had the return for each plumbed into the smaller vent that runs along the fuel filler neck. Now I have the fuel dump into the fuel sender. Fuel going to the pump comes from a bung I welded to the bottom of each of the tanks.

Jess

 

the way I would do it is to get another Selector valve and pig tail.
same one that is used currently on your truck.
cut and splice the new pig tail to the current harness match wires color to color.
make the second one to be used by your return line.
run the return line to the selector valve output side and the 2 feed sides of selector valve lines to your gas tanks according to what is running at the time.

basically reverse flowing through the 2nd selector valve.

as shown in the link below you can use the filler neck setup to run the return lines to the appropriate tank. being used
https://www.ford-trucks.com/forums/1...l#post17814626

your one flip of the dash selector switch valve switch will now change both the fuel supply tank and return line selector valve at one flick of your dash switch.

I hope it makes sense.

The only issue I can see is if there is a check valve or one way check valve in the selector valve preventing reverse flow.

 

Just out of curiosity, I've replaced a fuel filter on a 2005 Ford Ranger that had one inlet from the tank side, one outlet to the engine and one return inlet. The return goes right back into to outlet of the filter. Could this work right after the OEM tank selector valve?

 

Hmm, I don't see why not. It's just a different way of doing the same thing, but without all the added plumbing going all the way back to the tanks.
Similar to a reservoir like we used to use. Low pressure pulling from the tank to fill the reservoir, high-pressure pump to pull from the reservoir and supply the engine. Return went to the reservoir and then fed back to the engine as needed.

I've seen older systems where the filter's extra fitting was the return OUTLET and then back to the tank, but never where it was an INLET back from the engine.
But seems like it should work.

Regarding the earlier questions though, you must return the fuel to the same tank it's being pulled from.
This is because at lower load/rpm levels, probably the majority of the fuel is being returned. While you're idling the injectors are not opening up and putting much fuel into the engine, so most of it is going back around to the tank.
This Ranger filter SlikWillie posted up would eliminate that as even an issue. But if you use full returns to the tanks, it's gotta go to the tank in use.

Paul

 

i have the same dual tank setup with the 38 gallon rear tank and like this idea. But I can’t find a pump on their website that will work with the lock ring style instead of 5 bolt , and one that is deep enough. Do you have to know specifically which pump worked for you?

 

I used the Tanks Inc fuel pump that requires a big round hole be cut in the top and has conventional hose clamps instead of the push on style. Can't remember the exact part number of the pump I used, but they definitely offer one for a tank this deep. It has been trouble-free for many years, but is kind of loud in operation.

David