The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Ls swap dual tank, fuel system parts list, for return rail system???

izzy_Britton · 03-27-2016, 11:45 PM

Sorry to revive an old thread but i too have had some questions on this and i am not able to get hard definitive answers. I am going to go ahead and give my thoughts and theories here and maybe someone can straighten us all out.

This is my plan:

87 tanks

87-91 sending units with pumps attached (pumps replaced for higher flow versions maybe).

87-up fuel tank selector valve (under the cab not the dash mounted button)

03 corvette fuel filter with built in pressure regulator

so basically (i think) it goes like this:

(basic operation) The in-tank fuel pump with pump fuel from the tank, thru the tank selector switch, to the usual connection on the switch. then the fuel will continue to the 'vette filter regulator, then on to the engine.

Seems logical so far.

The 'vette filter regulator will return fuel back to the switch mech. and the switch mech. will return the fuel back to the proper tank.

plumb the 'other' tank exactly as the first with the lines inserted into the 2nd tanks ports on the tank selector switch.

so in the above scenario using the OE/replacement 87-up parts and placing the 'vette filter regulator combo device between the fuel tank selector valve and the engine, everything SHOULD work as it was originaly designed to work. the return line from the vette filter regulator would simply return fuel back to the tank selector valve exactly as it would have on a stock carb'd or TBI setup.

Anyone with experience in this matter see any fault with this set up?

Assuming the above is correct, the only real conundrum that i am having is the wiring portion. On the 87-up trucks, the trucks are wired for in tank pumps, changing sending units and pumps should be a plug and play situation. My truck is a pre-tbi so therefor my truck is not wired for electric in tank pumps. so i have no idea how the pumps are wired nor how the dash switch is wired for the pumps to kick on.

I would also assume that the pump that is in the non-selected tank is not running?

anybody?

thanks in advance.

-Izzy

03-27-2016, 11:45 PM	#7
izzy_Britton Registered User Join Date: Apr 2013 Location: Nor-Cal Posts: 632	Re: Ls swap dual tank, fuel system parts list, for return rail system??? Sorry to revive an old thread but i too have had some questions on this and i am not able to get hard definitive answers. I am going to go ahead and give my thoughts and theories here and maybe someone can straighten us all out. This is my plan: 87 tanks 87-91 sending units with pumps attached (pumps replaced for higher flow versions maybe). 87-up fuel tank selector valve (under the cab not the dash mounted button) 03 corvette fuel filter with built in pressure regulator so basically (i think) it goes like this: (basic operation) The in-tank fuel pump with pump fuel from the tank, thru the tank selector switch, to the usual connection on the switch. then the fuel will continue to the 'vette filter regulator, then on to the engine. Seems logical so far. The 'vette filter regulator will return fuel back to the switch mech. and the switch mech. will return the fuel back to the proper tank. plumb the 'other' tank exactly as the first with the lines inserted into the 2nd tanks ports on the tank selector switch. so in the above scenario using the OE/replacement 87-up parts and placing the 'vette filter regulator combo device between the fuel tank selector valve and the engine, everything SHOULD work as it was originaly designed to work. the return line from the vette filter regulator would simply return fuel back to the tank selector valve exactly as it would have on a stock carb'd or TBI setup. Anyone with experience in this matter see any fault with this set up? Assuming the above is correct, the only real conundrum that i am having is the wiring portion. On the 87-up trucks, the trucks are wired for in tank pumps, changing sending units and pumps should be a plug and play situation. My truck is a pre-tbi so therefor my truck is not wired for electric in tank pumps. so i have no idea how the pumps are wired nor how the dash switch is wired for the pumps to kick on. I would also assume that the pump that is in the non-selected tank is not running? anybody? thanks in advance. -Izzy __________________ WHO_DCTC - Wifes 05 Z-71 Build - Now defunct as she decided she wants an Escalade too Cream Puff - LS'd Square - Slow going on the back burner Tripple Threat - 3 Wrecks for the price of one build thread Project Delongdium - Step-Sons Plastic Clad 2003 Avalanche - DONE and Delivered.