Tank replacement for EFI

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scenic760

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You can't use the 87 pump, they don't put out enough pressure for the aftermarket efi. Use one from a 96 on the 87 sending unit to get the proper pressure, as long as it's a fairly stock engine.

Thanks!

Quick question, do you know if the '96 sending unit will work in the '87 tank? It's about 1/2 the price for whatever reason and looks very similar?

Your my boy Blue! (hopefully the movie reference comes across, haha)
 

Doppleganger

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When I collected the FI parts, I found that there are (2) versions of the EP381. One is cheaper and Made in China. The other is made in Brazil and about $100. Even though both are in Delco boxes, the latter is highly recommended.
 

bluex

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Thanks!

Quick question, do you know if the '96 sending unit will work in the '87 tank? It's about 1/2 the price for whatever reason and looks very similar?

Your my boy Blue! (hopefully the movie reference comes across, haha)

No you have to use the 87 sending unit. Unfortunately they have doubled in price over the last year or so.
 

scenic760

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No you have to use the 87 sending unit. Unfortunately they have doubled in price over the last year or so.

Seems like everything has!?

Do you know if I can use the MSD fuel pump that comes in the kit with the sending unit?
 

bluex

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Seems like everything has!?

Do you know if I can use the MSD fuel pump that comes in the kit with the sending unit?

No external pumps are not made/rated for submersible use
 

chief_shotts

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For anyone going down this path below is what I did with help from member Bleux and others for my 1977 K10. Prices below are as of today from RockAuto.

2 - ACDELCO EP381 {#25163473} (Pumps) - $57.79 ea.
2 - SPECTRA PREMIUM GM11C {#471681} (Tanks w/ Lock Rings) - $76.69 ea.
1 - SPECTRA PREMIUM FG05N {#25090837} (Passenger Side Sending Unit) - $73.79
1 - SPECTRA PREMIUM FG05M {#19179694, 25090846} (Drivers Side Sending Unit) - $66.99
1 - ACDELCO U7001 {#12336291} (Fuel Selector Valve) - $77.79
1 - STANDARD MOTOR PRODUCTS DS1807 {#15599081, 19244972, D7089C} (Tank Selector Switch) - $9.37
2 - Filler hoses to fit 1987 tanks - Can't find the part number

Notes:
  • Had to make a slight modification to reduce the 87 filler hose to the 77 filler neck
  • Used the sniper pump power lead to power the switch so my selected pump only runs until prime is finished before I start it up
  • Had to make modifications to the back of the selector switch to fit in the dash and be flush
  • Shouldn't have purchased the full Sniper kit as I'm no longer using the inline pump
  • Looks completely stock
This is awesome info. Thanks
 

1979 K10

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just purchased sniper 2 kit which comes with external pump, regulator and hose. My 79 K10 has the dual 16 gallon side tanks. I just installed a 500hp blueprint 400 crate engine. I’m guessing I can’t use the 96-99 vortec in-tank fuel pumps?

If I go with the external Holley pump, can I just run the return to the vent hose on the tanks? I purchased the 6 port fuel selector valve FV5T aka U7001. Will this work with the high psi return of efi?

It says not for fuel injection but I was going to put the pump after the valve so the only pressure the valve would see is the return fuel on its way back to the tank.

Currently have the original 3 port valve with no return and just vent hoses on tank.
 

SquareRoot

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I'm running 98 vortec pumps with my PF4 system at 53 psi thru the 6 port valve without issues. Been dead reliable for 2 years now. Make sure any rubber hoses are FI and ethanol rated and use FI hose clamps. What's your plan for a regulator? I assume you know you need 87 tanks and hangers and will have to fabricate a simple harness for switching the pumps? I've done it both ways. The in tank pumps are far superior than the external pump
 

1979 K10

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Hmm, I seriously considered the pro flo 4 system but I just put a rpm intake on my new motor and got the sniper 2 complete kit for $1500 out the door. I guess I could resell the Holley pump if I don’t use it. The sniper 2 kit I got came with a Holley external regulator.

I am going to keep my hei distributer as I already have it dialed in with vacuum advance and full mechanical at 32 degrees at 3-3.5k rpm.

I thought if I switch to 87 tanks the only issue is the filler hose size is different?

If I go 87 tanks with in tank pumps, how do I hook up the new 6 port switch? Guessing I need a 87 fuel tank switch and wiring harness to 6 port valve since my 79 valve has one wire.

What’s the downside of the Holley external pump? Just noise? Seems like the dual pumps are a lot of wiring?

I also thought about ditching the side tanks and putting a plastic suburban tank from 96-99 vortec where my spare tire would go? I have a tow hitch now but no spare.

Or just run one side tank for now?
 
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SquareRoot

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87 tanks are baffled inside. Uncover an intake pump pickup and the engine will die instantly. You are correct about the filler hose but LMC sells them for cheap. Just duplicate the harness from any dual tank truck with the 6 port switch. It's simple but it will only switch the valve and gauge. You have to add a switch and relay to control the pumps now. In tank pumps never lose prime, run cooler, quieter and last longer.
 

1979 K10

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I think I’ll order a 87 tank for the driver side and use the vortec truck in tank fuel pump if it will support my 500 hp motor. Or will use this pump sometime mentioned here https://www.summitracing.com/parts/aei-11569

I’ll just bypass the valve and wire and plumb the driver side tank as a single tank. I currently have a low pressure electric fuel pump for the carb. I’ll use that as a transfer pump from the passenger side tank and wire that to a switch to move fuel from passenger tank to driver when needed. Just need to figure out how where to plumb hose to as another inlet on driver tank. Then I don’t have to buy another in tank pump for passenger tank and can just leave that tank as is.
 

1979 K10

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Looking at rockuto for a 97 k1500, these pumps are offered:

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'87 Fuel senders
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SquareRoot

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The pickup unit has to match the tank. You need a pickup for an 87 tank. It will have three hose barbs. 3/8 inlet, 5/16 return and 1/4 vent. Buy just the pump for a 96-98 and switch it with the one on the 87 unit. They are interchangeable physically but have the pressure needed for efi.
 

1979 K10

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@SquareRoot I really appreciate your help!

I updated my previous post and will probably go with:
Delphi FE0114 pump
Dorman 692044 sender? - Seems like this is the only sendor for a fuel pump.

Or order a TBI pump housing assembly and swap out the pump?
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SquareRoot

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@SquareRoot I really appreciate your help!

I updated my previous post and will probably go with:
Delphi FE0114 pump
Dorman 692044 sender? - Seems like this is the only sendor for a fuel pump.

Or order a TBI pump housing assembly and swap out the pump?
You must be registered for see images attach
Lol. Very ironic I'm working on my setup today. I just never got around to installing the second tank after rewiring and checking everything. My truck is the second truck I've done this mod too. I used my buddy as the guinea pig. Lol
 

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