1976 k20 gas tank swap

crusty_jalapeno

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Walla walla Wa
First Name
Mark
Truck Year
1976
Truck Model
K20
Engine Size
400
Hi folks, so im about to start the project i mentioned in my introduction post. She is 1976 K20 with crate 400, 69k miles on odometor. 200 4r transmission. There are some questions(tried to read as much as possible, have a general idea how to do it).

I need help with the shopping list if you may. I want to take down 16 gal tanks and replace them with 20 gal tanks.
I am thinking of adding EFI comes summer time.so far as parts go i know i need

GAS tanks x 2
Sending units x 2 (for each side)
2 rings
4 new straps
Electric fuel pump?
What else am i missing?

I ll be gratefull for any advice. This saturday im taking old parts out, but would like to order before then. Thank you guys.
 
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Grit dog

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Todd
Truck Year
1986
Truck Model
K20
Engine Size
454
Consider separate pumps in each tank. Although 1 good pump set up right will doo the trick.
Filler and vent hoses
Anti squeak material.
New fuel hose, 3 sizes.
Possibly tank mounting hardware.
 

oldretiredafguy

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350, 350, 350, 350
Make sure you get the replacement tanks built for 1987 and up trucks. They have baffles, and are set-up to handle the high pressure fuel pumps required for TBI/EFI. Also, the fuel tank selector switch is different for 81-86 carb trucks and 87 up TBI vehicles.
 

scrap--metal

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Calvin
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'85, '81
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K10, K20
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305, 350
I want to take down 16 gal tanks and replace them with 20 gal tanks.
The rubber filler necks to connect the the tank to the side of the box are different length when using 16 vs 20 gallon tanks. You can probably shorten the rubber sections that you have, but I've just replaced them.

Also, make sure your rubber filler neck is the correct diameter for your new gas tanks. Early trucks used a smaller diameter neck on the fuel tank than the later squares.
 

scrap--metal

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Location
MN
First Name
Calvin
Truck Year
'85, '81
Truck Model
K10, K20
Engine Size
305, 350
Make sure you get the replacement tanks built for 1987 and up trucks. They have baffles, and are set-up to handle the high pressure fuel pumps required for TBI/EFI.
IDK about the '87 tanks with internal baffling, but the '82-'86 tanks without baffling use a larger different diameter neck on the fuel tank than what would've originally been on his '76.
 

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