dual tanks with late model EFI?

[Fishandgame]

Originally Posted by Desert1957

I thought about this idea on my crew cab , but it would be the lowest thing hanging down . not sure if you have an issue if you could ever stop the fuel flow to the ground.

I thought about that and considered a ball valve at each tank. It wouldn’t have to sit too low if the bulkhead attached to the tank bottom were cast or shaped nearly flat. And the manifold pipe was slender and wider. The bulkhead could even have a curve matching the tank bottom leaving the tank the lowest still. It doesn’t take much in pipe diameter. I used 3/4 PVC on my water barrels and the level stayed even between both as fast as a full flowing garden hose could put it in one. Even if the fitting opening was an inch or so above the bottom line of the tanks who cares. So you don’t get a gallon out of the tank without the pick up. You don’t get that anyway with the pick up tube or really don’t want to get it since any water goes to the bottom if there were any. So 19 or 39 gallons if both tanks are 20 gallons. I’ll have to research a weld in bung fitting to accept an AN fitting. Heck it could be any fitting type so long as it sealed fuel. I almost have myself talked into trying it. As long as you could route the line across the chassis without having any part above the lower tank bung it would work. A couple service valves and presto. My chassis is in blasting and paint. I’ll look at it when I get it back.
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[donw1986]

The later model c10s from i think 83 to 87, i have a 86, the transfer valve can handle up to 65 psi iinstalled a msd efi on my 86 put a pump in each tank and wired the power to the pump through the switch on dash using an 87 switch, if you have an 87 should be easy the early model c10 had a low pressure valve but new is good to go

[Ford Assassin]

Another run at the top.

How about using in-tank TBI pumps, through external filters, then to the switch tank valve, then into the high pressure pump, the to a regulator, then into the fuel rails?

[layinrocker65]

I have about 20k miles on the dual tank setup in my 74. Used EFI tanks with the pumps in the tanks, the soft EFI rated fuel line to the high pressure valve, then to a corvette fuel filter regulator, then a single line up to my LS rails. I can switch tanks on the fly without even noticing.

The only issue I’m having now it that my newly installed Dakota digital RTX gauges don’t seem to like the fuel signal going through a switch so it doesn’t read correctly. Had no issues with the stock gauges. I track my mileage(~20mpg) so it’s not a huge deal right now but I need to figure it out.

[Ford Assassin]

Originally Posted by layinrocker65

I have about 20k miles on the dual tank setup in my 74. Used EFI tanks with the pumps in the tanks, the soft EFI rated fuel line to the high pressure valve, then to a corvette fuel filter regulator, then a single line up to my LS rails. I can switch tanks on the fly without even noticing.

The only issue I’m having now it that my newly installed Dakota digital RTX gauges don’t seem to like the fuel signal going through a switch so it doesn’t read correctly. Had no issues with the stock gauges. I track my mileage(~20mpg) so it’s not a huge deal right now but I need to figure it out.

I was hoping to avoid buying two more pumps since I already own a Walbro 255 in line from another project. Hence using the stock in tank TBI pump(s) to feed the in line Walbro.

I have the VHX Dakota dash and haven't had any issues with the fuel gauge.

[layinrocker65]

It’s been so long since I did the swap but I’m pretty sure I used the TBI fuel pumps I’m my tanks. I previously had an in line walbro and hated it. Too loud. There is no reason to feed an in line pump with an in the tank pump. Your just over complicating a pretty simple system.

[Ford Assassin]

Originally Posted by layinrocker65

It’s been so long since I did the swap but I’m pretty sure I used the TBI fuel pumps I’m my tanks. I previously had an in line walbro and hated it. Too loud. There is no reason to feed an in line pump with an in the tank pump. Your just over complicating a pretty simple system.

No way you ran stock TBI pumps feeding a LS 4 BAR (58 PSI) system. Stock TBI 87 is a 13 psi system, not even BAR 1.

I appreciate your response, but how am I overcomplicating when I just wanna add a single in line pump to an existing setup? Seems like the LEAST complicated (and most cost effective )way to get it done.

Fuel pump noise doesn't bother me, most can't be heard when the vehicle is running anyway. I am running dual Bosch 044's on my turbo K5 and a Magnafuel 1000HP rated pump on my drag car. That pump is loud, like 2 stroke chainsaw loud.

[marcoman]

Originally Posted by layinrocker65

It’s been so long since I did the swap but I’m pretty sure I used the TBI fuel pumps I’m my tanks. I previously had an in line walbro and hated it. Too loud. There is no reason to feed an in line pump with an in the tank pump. Your just over complicating a pretty simple system.

Wow, so where did you get those pumps from? I'm curious because I have an '84 GMC shorty and plan to do an LS powerplant in the future. BTW You guys are a great resource!

[naphtali5725]

anyone ever used one of these?

https://www.robbmcperformance.com/pr...owersurge.html

[hatzie]

Originally Posted by naphtali5725

anyone ever used one of these?

https://www.robbmcperformance.com/pr...owersurge.html

That's essentially an expensive surge tank with a built in fuel pump. You probably still need a pressure regulator if you can't request a specific fuel pump.

A surge tank system uses the in-tank pumps as lift pumps to keep the surge tank filled. The stock pumps will flow more GPH at the lower pressure demanded to keep the surge tank filled. 5-7PSI is what I'd guess the pressure in the surge tank will level out at. I bet the TBI pumps that normally run twice that pressure will flow plenty of fuel to keep the high pressure pump happy. They'll run cooler with the higher flow and lower pressure as well.

You can build your own.
The surge tank should have four fuel lines.
-A feed and return to-from the engine for the high pressure EFI system. You'll get more fuel returned than you might think.
-A low pressure fill and return from-to the tank(s).
-A high pressure fuel pump.

You should be able to mount the surge tank in the engine bay to keep it safe from road debris. Tuck it down by the battery tray and the radiator support to hide it.

You can run the stock dual tank valve and lines with a modern EFI setup using this configuration.

As noted earlier on. You could also use the stock dual tank setups from the LS powered vans that used the PCM to control the tanks as if they were one tank. You'll likely have to roll your own fuel pump/sender module mount for the donors fuel pump/sender modules.

[naphtali5725]

thanks hatzie!