hey im new here.

this seems like the impossible but i have put a 1978 model350 in a 89 model lt came with the 2.8. i have the engine int he car and runnin and u can drive it thanks to my electric fuel pump and gas jug.i know not safe lol.
so i have to questions what do i need to do with all this extra wiring
and why cant i get fuel from the tank

 

Welcome to thirdgen.org.

Most likely in the process of removing the V6 and installing the V8 (not that uncommon for an older 350 to be in a 3rd gen, by the way), the wiring that powers the in-tank electric fuel pump was disabled. Even if you have a mechanical pump on the engine, pulling through an inoperative electric is chancy at best.

You need to provide ignition-switched voltage to the pump in the tank. Going through an oil pressure switch is a good safety precaution. You'll also need a return-style fuel pressure regulator like a Mallory 4309 to lower the pressure to a carb-safe 4-7 psi.

 

thanks alot
what should i do with all the rest of the wireing that is not connected to anything

 

you should carefully take it out. Start at the ECM (take it out, too) and then work your way out to the engine compartment. The harness goes through the passenger side front fender and then into the engine compartment.

Then put the whole V6 setup for sale here or on eBay with no reserve and a .99 cent starting bid. Let it go to whoever needs it. There are actually people here who need that harness to fix theirs because it was damaged.

You'd be surprised!

Oh, and welcome aboard!

 

Might want to rethink yanking wiring just yet. I left my wiring in tact when I got rid of my computer and went carb - I used alot of my wiring for other things. Like the elctric choke, adding fog lights, adding a manual fan switch, adding a manual TCC lockup switch, and many other things. I use the wiring from the ECM to get power into and out of the interior, without having to drill new holes and make a mess through the firewall. Things with large power drains (like fans and fog lights) I rig with a relay, so the power going through the old ECM wires is just to power up the relay.

Plan ahead before yanking. You can always remove unused wires, you can't put them back!

BTW - my 350 is from a 1969 Camaro lol

 

If I take the ecm out will my gauges stil work?
The only wiring i need is the wireing comein out the drivers side. Right?
What about my fuel pump in the tank, what do I need to do with it. Rewire it or what? Thanks alot

 

Your gauges are not run by your ECM, they'll be ok. I'm sure some of your heater wires and such also come from the passenger side so don't just hack everything! You really have to go through it carefully!

Believe it or not, your fuel pump will run off of the oil pressure switch after your engine is on if you wire it up correctly. You can also run the fuel pump relay with an "ignition on" wire instead of the ECM.

The only right way to do it is to pull the tank and take out the electric pump and use a carburetor sending unit, or replace your pump with a hose or tube so that you can re-use yours.