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Old 12-01-2018, 07:52 PM   #1
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Aftermarket F/I and dual tanks 81 K30

I was looking at an F/I system with the fuel pump in a small tank in the engine compartment thinking that would save me from 2 in tank pumps and return lines but it looks like it still uses return lines. I have no return lines now.

I also have an 87 parts truck with dual tanks. Did those TBI 87s have pumps in the tanks that might be compatible with an aftermarket system?

Any advise or recommendations please. What have you all done?
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Old 12-01-2018, 08:15 PM   #2
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Re: Aftermarket F/I and dual tanks 81 K30

What is the fuel pressure in the aftermarket system?

Some new Pollack dual tank valves are rated at 65PSI but that's the limit using the near stock valve.

You can install higher pressure and higher volume Walbro fuel pumps in the tank but it's not plug N play. You need to modify the electrical connection to the fuel pump.
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Old 12-01-2018, 10:11 PM   #3
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Re: Aftermarket F/I and dual tanks 81 K30

i just finished this kind of setup . i kept it stupid simple .

2 tanks . pic a side for primary with psi pump specs the efi needs . it gets the job of the efi system only .

other tank is a transfer tank with a std tbi pump on it .

send fuel over to the other primary tank and tee in to the filler neck vent hose right at the tank as its all up hill from there to the filler neck / cap area . fuel has to go down hill in to the tank .

next i rewired my indash switch for power feed out only to transfer tank .

next i installed a seperate gauge ( if you want one ) and a BIG red light that only lights when pumping fuel over .

i tried it for the first time yesterday and was impressed . no waiting in line at the fuel station just pic a pump with 2 tanks . just so happened i had pass side open and mine is the transfer tank on the pass . i filled it up full . took off down the road and flipped my switch and in 5 miles my driver side tank went from 1/8 to 3/4 tanks .

this is just my simple what i had version and do as you wish . good luck and remember to double check them fuel lines for leaks
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Old 12-03-2018, 02:53 PM   #4
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Re: Aftermarket F/I and dual tanks 81 K30

depending on your flow requirements, the selector valve should work- it'll switch the feeds, returns, and senders.
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Old 12-03-2018, 09:33 PM   #5
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Re: Aftermarket F/I and dual tanks 81 K30

i've been running an edbrock pro-flo on my 454 for over 15 yrs. ('85 K30 crew)
i also have dual tanks as well. my vent lines stayed vent lines, the orig fuel line became my return, and i used a bigger line for the fuel. all the lines hook right up to the selector switch, so it functions just as stock, and i used the external fuel pump that came with the system, it's installed on the frame in front of the selector switch. in all the time i've had the p. flow, only thing i've done to it is replace the fuel pump once, couple yrs ago, which was my fault, too far out in the bush and had to run my tanks almost empty to get back to civilization....
in cab switch and fuel gauge work as they should, no probs
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Old 12-03-2018, 10:28 PM   #6
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Re: Aftermarket F/I and dual tanks 81 K30

I recently ran a sniper (60 psi) in my 85 with dual tanks. I used the Edelbrock remote sump mounted near the driver side headlight. Ran the stock mechanical fuel pump to the sump and a high pressure line to the sniper. Worked like a charm. Didn't have to mess with the original tank, valve or wiring.
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