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Dual External Fuel Pump Plumbing for 4400?

Shutoff goes on the outside, as close to possible to the tank. It's here to kill fuel flow manually.
 
Comical that you thought it was on
The suction side! Wtf man
I thought you were saying they required a shutoff between the tank and pump like the diagram Mobbil1Syn posted regardless of whether in tank or out of tank.
 
I am currently fighting to put the pumps in the tank, it is a pain in the ass but i is what you are supposed to do. In my bouncer i had the pump external, but i drill to hole in the bottom of my fuel cell and put the bulkheads there. The pumps where always flooded unless i shut the manual valves. No room for that setup in a 440o car.

why is it a PITA?

I thought you were saying they required a shutoff between the tank and pump like the diagram Mobbil1Syn posted regardless of whether in tank or out of tank.

i want the valve to be the first thing out of the tank, easily accessible even when flipped, labeled well enough that any idiot near the car can shut it off
 
This whole thread is a lesson in how to over complicate things lol

Which is the exact opposite of what I was trying to do! The goal is to make it work like a champ and be as simple and easy to work on as possible. I had no idea I was making it hard.
 
i want the valve to be the first thing out of the tank, easily accessible even when flipped, labeled well enough that any idiot near the car can shut it off

usually they are installed same color as everything else, not labeled, and super small so you can't find the stupid off lever. I fully agree on the above.
 
i want the valve to be the first thing out of the tank, easily accessible even when flipped, labeled well enough that any idiot near the car can shut it off
Yeah if I had a shutoff that's where I'd want it too, especially if the tank had a gravity outlet on the bottom.

Maybe run a traditional form factor ball valve and pull the handle with a push/pull cable mounted somewhere near the rear like on a drag car or run it up to beside the electrical stop button?
 
I don’t know much about those, but if they are brushless can they be put inline? For the horsepower those are rated that I’m sure you could let the one in back push through the one in front and it should freely spin. If a drop in and pressure is detected, you could have a switch kick on the one in front?!?!
 
I don’t know much about those, but if they are brushless can they be put inline? For the horsepower those are rated that I’m sure you could let the one in back push through the one in front and it should freely spin. If a drop in and pressure is detected, you could have a switch kick on the one in front?!?!

when a pump fails they usually self destruct, so when it comes apart it sends it down the line, in your setup you now clogged the system losing your redundancy.

the pre filter is to protect the pump, post filter is to protect the injectors
 
I guess i just hate working down in that hole. The wiring makes me nervous also, what if you have a short? I am doing it , it just sucks to me.
 
I guess i just hate working down in that hole. The wiring makes me nervous also, what if you have a short? I am doing it , it just sucks to me.

there are plenty of easy off the shelf solutions.

90% of the cars on the road have the pump inside and that ls motor everyone runs has an intank pump that soccer moms have rolled into gas stations after dropping sally off at ballet on fumes. i am idiot and ran 03 tahoe put of fuel, chased wiring, finally swapped a fuel pump to find i there was a 1/4 cup of fuel in the sump and the bottom of the tank was dry. felt like a complete idiot, basic trouble shooting alluded me because i got hyper focused on the fact the guages wont move when the key was cycled.

in short your worries are misplaced.
 
I have nothing to add other than this picture I saw on the Tribe16 Facebook page that made me think of this thread.
A7A07938-2F76-4045-ABD5-E1073ED095C1.png
 
I have nothing to add other than this picture I saw on the Tribe16 Facebook page that made me think of this thread.
A7A07938-2F76-4045-ABD5-E1073ED095C1.png
dual 044. they have check valves in stock outlet banjo fitting. mounting them above tank lift pump must be used.
 
I have nothing to add other than this picture I saw on the Tribe16 Facebook page that made me think of this thread.
A7A07938-2F76-4045-ABD5-E1073ED095C1.png


That's also a really good example of how to hide a fuel shut off valve so nobody other than the person who installed it could find it.:shaking:

edit: On second thought, looks like it might be there so the driver can reach it. Doesn't look like it would be easy though.
 
Here’s a good one. Every koh winner, who had in tank and who had external.
 
Jason Scherer new car uses the same solution I posted above.
Something tells me he studied his options fairly well before committing.

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  • make sure your vent is filtered, for every gallon of dinosaurs that go out the tank, a gallon of dirty air goes in

That's an excellent point, whats the commonly accepted practice for the fuel cell vent with a filter? I heard Dave Cole say a few times at the rookie weekend that he prefers 3 sides and down and doesn't do anything crazy with catch can's for really anything but he never really talked about filters.

The fuel cell has
  • One AN-10 tip over valve vent fitting

You just run a line 3 sides and down and stick something like this on the end?


 
I run the cheap clear plastic fuel filters on the ends of all my vents. Been working for 15yrs.
 
You need a large vent if you want to fill fast.

for every gallon of dinosaurs that go out the tank, a gallon of dirty air goes in

The speed matters too. It's easy to have a big ass gas jug and try to send as much fuel as you can, but your vent needs to handle the same amount in the same time too. Better oversize that shit. AN-10 isn't big enough if you have a dump can.
 
What pushed me away from running in-tank pumps the last time I was setting up a tank was that I couldn't find any in-tank pumps that had threaded fittings on either end. Going in-tank seemed to mean clipping a sock on one end, and some sort of fuel hose on the other, while I wanted to run fittings and hardline - walbro pickups on one end, hardline out to fuel rail on other. Since I wasn't seeing what I needed I just went external and that was that.

I have another tank I need to plumb soon, and I'd like to go dual pumps in-tank, with hardline to hydramat on one end of the pump, and hardline out side of tank on the other. My main question is what is the main difference between an in-tank pump and an external pump? What happens if you run an in-tank pump outside the tank - other than it being a pain in the ass to attach to the inlet? What happens if you run an external pump submerged in fuel? :nuke:

I talked to someone at Holley who had no idea not too long ago (surprise). Last time I was ordering fittings from G&J Aircraft I asked them and was told that they'd been running an A series Aeromotive external pump in-tank for years on one of their cars with no issues, and didn't have much to say other than that. I suppose the next call should be to Aeromotive directly, but I never got that far...

My last setup that I pussed out and went external - put a 1500 psi check valve in-line after each pump before it Y'd back together. If going in-pump, might be good to have checks and Y happen outside tank for easier diagnosis if pump not responding?

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Not sure if any of that is helpful or if I'm just posting random thoughts. I will say though, for anyone needing to order fittings - I've found that if I draw out my plumbing schematics on paper with all types/sizes of fittings, I can just email that to G&J Aircraft and they will piece my order together

IMG_8231.jpeg

edit: Another random thought - another difficulty I found when wanting to plan out an in-tank pump setup, is it seems every mfg option is to have pumps and pickups mounted to the top plate. If you're running baffles in your tank, that means you have to smash pump/pickups into your baffles as you bolt in the top plate, which doesn't make any sense to me. What makes sense is to have your pumps mounted in the tank, pickup mounted in the tank, hardline connecting everything - all separate from top plate. Baffling can be packed in and top plate installed, and it's all separate and clean:homer:
 
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didn't read the whole thread. my setup is 2 internal Bosch 044s ran one at a time for redundancy for a stock bottom end, heads & cam LS3. just socks on the pumps no hydramat or one way pickups. each pump has an external check valves mounted to the outlet. they Y together to one line outside the cell, through a fragola filter, then to the ball valve on top of the cell and out to the regulator (AEM 13101). Vent is a -16AN rollover valve from Harmon racing cells, 1" heater hose routed 3 sides and down. works OK with my dump can. fills fast enough for me. my cell is big enough that I usually don't have to pit for our races.

it works really well. each pump has it's own breaker (no fuses) and it's own relay. the relay coils are both powered by the 12v fuel pump signal from the pcm, and the pumps are switched electronically by grounding each relay coil separately through an on/off/on switch in the dash.

I've simulated fuel pump failure by removing a pin from the wiring connector with the engine running, waited until the engine began to lose fuel pressure, then switched on the other pump and it worked perfectly every time. never had a pump fail in a real world scenario but it's good to know the system works should a failure occur.

only change I would make is flow-through rails but I haven't experienced vapor lock yet with the factory dead head rails. my fuel lines are very well isolated from external heat.
 

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What pushed me away from running in-tank pumps the last time I was setting up a tank was that I couldn't find any in-tank pumps that had threaded fittings on either end.
This is intentional. They want a hose on the business end because the don't want you loosening the pump from whatever structure hangs down from the flange to support the pump in order to barely getting it lined up with your crooked-ass hard lines and then cranking everything down tweaking the end of the pump and then bitching at them on twitter when it fails in 2mo.
 
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