EFI Dual Tank Conversion, need help on power 4 the pumps.

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SquareRoot

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Got the 87 tanks, sending units, ep381 pumps, pollack 6 port motorized valve and tank selector valve installed.

How are folks powering the pumps?

Tapping into a hot wire on the sending unit?
Running a dedicated power wire and dual relays?

Help a brother out. Thanks
 

Vbb199

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Doesnt the pro flo have a relay or some sort of fuel pump trigger?
 

Vbb199

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Stupid on my part, i misread your question, sorry about that! Whats wrong with tapping into the hot wire of the sending unit you already have?

Also, im kinda intrigued in this, i'd like to add a second tank to my 79... that little 16 gallon aint gonna last forever with my gas guzzling h u s s y
 

dvdswan

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Here is both (wiring and lines) for you...

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SquareRoot

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Here is both (wiring and lines) for you...

You must be registered for see images attach

Thanks! Looks like I just tie into the positive feed on the sending unit. I just wasn't sure how many amps those pumps would be pulling thru the existing wires. I did find that EP381 pumps draw 9.5 amps if deadheaded and 5 amps at 45psi. I'm running #43 psi so I should be fine. No relays needed!
It's important to note for others reading this, that you MUST use the newer 87+ 6 port valve otherwise when you switch tanks you momentarily lose power (fuel) and the engine stalls. The older valves don't have the "overlap" nor the capacity to handle the higher pressure.
 

SquareRoot

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Stupid on my part, i misread your question, sorry about that! Whats wrong with tapping into the hot wire of the sending unit you already have?

Also, im kinda intrigued in this, i'd like to add a second tank to my 79... that little 16 gallon aint gonna last forever with my gas guzzling h u s s y
Yep, that should work. Just wasn't sure on the amp draw of the high pressure pump going thru that OEM size wire. Found out it only pulls 5 amps @ 45psi.
 

SquareRoot

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Got the Russell fuel line and -6 fittings today to connect the Aeromotive regulator to the fuel rails. Did you know there isn't 5/16" AN fittings except for a hose barb adapter? Also got the 2 port pico weatherpack connectors to plug into the new sending units. I'm a little anal about doing things "correct". Tired of doing **** over and over again because I cheaped out. Lol.
 

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SquareRoot

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Also...the 87 tanks have the larger inlet neck that actually fit the fuel filler hoses that everyone sells. Spectra FNH169. Right or left, fits both sides.

Carry on
 

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SquareRoot

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Just waiting on the anti-squeak strips and vent hoses and should have everything for a 100% OEM conversion.
 

Vbb199

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Also...the 87 tanks have the larger inlet neck that actually fit the fuel filler hoses that everyone sells. Spectra FNH169. Right or left, fits both sides.

Carry on
good ****... i ended up with some generic gas neck and cut it down to fit.
 

Vbb199

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Yep, that should work. Just wasn't sure on the amp draw of the high pressure pump going thru that OEM size wire. Found out it only pulls 5 amps @ 45psi.


I was wondering, i ran an oem tbi fuel sender/pump line down my frame to power my fuel pump, and tied it into the holley's relay. Seems ok for now.
 

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Just waiting on the anti-squeak strips and vent hoses and should have everything for a 100% OEM conversion.
I ordered anti squeak strips for mine. They were on back order for like 2 months. After I got sick of waiting I cut a couple strips of ice n water shield (rubber roofing underpayment) and used them. Worked great. Now I have an unused set of squeak strips….
 

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Got the Russell fuel line and -6 fittings today to connect the Aeromotive regulator to the fuel rails. Did you know there isn't 5/16" AN fittings except for a hose barb adapter? Also got the 2 port pico weatherpack connectors to plug into the new sending units. I'm a little anal about doing things "correct". Tired of doing **** over and over again because I cheaped out. Lol.
I would definitely use a relay for the fuel pumps. That is the "correct" way. Good luck
 

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