1988 GMC C1500 engine/trans into 1973 C20 Crew Cab

[jim_in_dorris]

#2 first. That pcm will not live in the engine compartment. it was designed to go behind the glove compartment in the cab. under the front seat would work fine.
#1 if you T the line into the feed, you will have pressure on both sides of the pressure regulator and it won't work. The return line needs to run all the way back to the tank. OOPs, i just re-read your post. I assume you have an inline pump for your fuel line. i am not sure if it would cause a problem there or not.

[PJG1173]

for the return line you can T into your filler neck. take a piece of 1 1/4 pipe drill a hole and slot it. then take a piece of 5/16 tube and weld/braze it at a 45* angle to the 1 1/4 pipe. as the return fuel comes back to the tank it will shoot right down the filler neck tube into the tank.

[O-B-1]

The truck has TWO tanks with a valve to switch between the two.

We are installing a E2182 in-line fuel pump. I was going to put an inlet (Purolator F21111) filter BEFORE the pump, then the pump, then fuel injection filter (FRAM G3727) AFTER the pump to catch any fines before they enter the injector.

I thought putting a tee between the line from the tanks BEFORE the inlet filter would allow the return from the regulator to return back before the pump.

I was thinking that if the return from the regulator just went back to the tanks there should NOT be any pressure to speak of unless there is some other mechanism at the tank to impede it's flow.

The inlet at the pump would normally create a vacuum...

I have one other question... The ECM has a signal that would come from the shift selector active when the selector is in PARK and NEUTRAL... how do I rig something like that?

Thank you for your help and ideas...

O-B-1

[fastacton]

You can get a dual tank selector from a truck similar to the donor (it switches the feed and return lines), but reliability might be an issue, mine never seemed to want to work right. I wouldn't tee the return into the feed line, it would might work, but I could see it causing problems that could drive you crazy as well.

Once you have the wire harness torn down, you might see that you can get enough length out of it without extending it. But if you can't, a van harness has tons of length built into it.

[O-B-1]

It looks like getting a 6-port tank selector valve and two of the Moroso filler neck adapters with returns is in order.

I still have to figure out how to get the park & neutral switch set up. Maybe magnetic reed switches in the linkage somewhere, or give her a switch on the dashboard.

[PJG1173]

switch on dash = bad Idea. magnetic reed switch now that's a new one. I'll have to remember that one it will probably work. I have a aftermarket floor shifter with the park/neutral switch built in so I wired into that one.

[garnerm]

How hard would it be to just mount the tank from the donor truck? ECM needs to be in the cab because it is not water tight. you could use a 1227727 ECM and it is made to be under the hood.