87 Silverado Fuel Questions or Will This Work ?

[HuntinNut]

My 17 year old son and myself are currently in the middle of a 81 SWB and have the 5.3 and 4L60 set in and waiting for his cab to get back from paint to start the plumbing and wiring..

In the meantime he just picked up a 87 Silverado with a blown sbc and the TBI has been replaced with a carb, the tbi lines are present and a regulator has been added to feed the carb using the in tank pumps. He needs the baffled tanks for his 81 build and we do have two non baffled tanks in storage as well as a good 305 roller motor.

Heres my question

I'd like to replace the tanks with the non baffled tanks and pull the pumps, but reuse the sending units with a pickup tube in place of the pumps. In my head this way I'd still be able to plug everything in and I'd just use the fuel pump on the block. Honestly it seems like the easiest way to not have to rewire anything and still have his duel fuel tank setup. Thoughts ?

[my86lb]

http://67-72chevytrucks.com/vboard/s...d.php?t=379708

[HuntinNut]

Originally Posted by my86lb

http://67-72chevytrucks.com/vboard/s...d.php?t=379708

Unless I missed something and I could have that doesnt answer the question I have above, but may be useful when I start on his other truck.

[sweetk30]

baffle or not if going efi just use baffle tank .

i have a 87 baffle tank with a tbi sender and a acdelco ep381 pump for a 1996 c3500 5.7 vortec engine . all direct clip and fit . this combo gives me the 60psi i need for aftermarket or stock ls based efi systems . all stock every day parts and quiet over external pumps and all the extra stuff .

i used a extra tbi tank and pass side tbi sender with tbi pump to transfer the fuel to the driver side via a tee fitting in the filler neck 5/8" vent hose . switch and light on the dash lets me know i am pumping . and only gets power when key hot .

whats your main goal ? ? give us more on this and maybe we can give you a better / cleaner setup than what you had planned .

[kwmech]

There was an OHM change in the senders sometime in the early 80s that may not allow this conversion

[sweetk30]

not that i have ever seen . gm for years and years has been 0-90 ohms .

[HuntinNut]

Originally Posted by sweetk30

baffle or not if going efi just use baffle tank .

whats your main goal ? ? give us more on this and maybe we can give you a better / cleaner setup than what you had planned .

To do away with the EFI and use the mechanical fuel pump on the motor we'll be installing. I have 2 non baffled tanks from another truck and would like to use the sending unit from the 87 with the pumps removed and a pickup tube in thier place. That way hopefully it be plug and play for the gas gauge.. I remeber reading a thread once before IIRC where a guy just removed the in tank pump and put a hose in its place to switch to a mechanical pump and carb..

The baffled tanks will be needed for his LS swap in another truck..

[Dead Parrot]

I think a few of us were confused as to which truck you were asking about. Sounds like this thread is about the 87 that will have a carb setup with dual tanks and any questions on the FI 81 will be in a separate thread.

I don't think there are any external physical differences in the gas tanks so the non-baffled should work fine in the 87 mounting setup as should the senders fitting inside.

On the senders, might see if a local parts place has the older suction style and compare to your existing 87 senders. If the only differences are the pump in place of sock, see about ordering a pair of socks. See if you can get a new rubber O-ring for the sender-tank seal.

If there is an in-line fuel filter between the tanks and the motor driven fuel pump, might replace with one setup for low pressure. You are switching from a system with pounds of positive pressure to one with negative pressure.

Might measure the filler tubes on the tanks in storage vs the ones on the 87 just to make sure they didn't change diameters.