need help bad on wiring my car

[surfsup]

Hey guys I need help I’m doing the 5.0 swap it's a 92 with the 2.3 the donor is a 85 I’m ready to install the motor but I have no idea on how to wire this thing, am I suppose to remove the harness that goes into the interior and replace mine with the 85 ? The mechanical aspect is a breeze but the wiring has me so confused I searched the archive and didn’t really find anything any help would be great

[Falcons Talon]

This is all I have. Hope it helps.

[crazypete]

If I remember correctly, there is 2 "harnesses": The frame harness and the 2 ecu harnesses. What you need is the eec harness and everything attached to it. I think they interconnect at 2 places but are independant otherwise. Pull the eec-4 and trace it's wiring forward to the firewall. It should be fairly isolated. I remember the harnesses were really well seperated when I ripped out all my EFI crap to turn my 91 into a carb.

If it's an 85....isnt it a carb already? That would _really_ simplify things: all you need is to rip out the 92's ecu harness and toss it. You might have to get an ignition box if this is the case (the 2.3's eec-4 and the tfi module controls the spark)....

[surfsup]

The 85 is carbed after I remove the eccu and harness then what? Do I run the 85 harness through the fire wall. Some one told me that I could run with the 92 harness I just have to make some minor changes but not really sure on what that means

Falcons talon thanks for the schematic

[crazypete]

I'm pretty sure the "chassis" harness is seperate from the engine harness functionally and runs along the back of the motor bay along the firewall. Disconnect the two big mother connectors at the back of the engine on the 2.3 (I am assuming they use two connectors like the 5.0's) and see if the lights and horn and turn signals work. Other than that, you dont need juice for a carbed motor.

You'll need to get an ignition box then since the TFI distributor uses the computer for an ignition controller. The 85 carbed motor will have a vacuum advance distributor but the coil needs an ignition signal from somewhere so a duraspark or MSD unit would be advised. If the 85 shell is available, gut the duraspark unit. It should be behind the battery location.

By the way, the in-tank 2.3 fuel pump wont work with the 85 motor. If the 85 motor has the pump on the side of the timing chain cover, you'll need to drop the tank and replace the pump with a length of hose slightly longer than necessary to reach the bottom of the tank (so it turns sideways when it hits bottom). Just thought I'd mention that since the fuel pump relay is computer controlled.

In my _humble_ opinion...this is the best time to pop the dashboard, kick panels, rocker panels and the rear interior panels and pull the extra useless 25 pounds of wiring and harnesses that ship with the fox bodies. You can reduce that forest of cabling to a single 1.5 inch across bundle of wire. Most of that stuff is for airbags and computer wiring. This way, you can trace the useful wires and cut everything else. This will let you move the wiring along the driver's side of the enginebay to the other side of the metal wall. It CRAZY cleans up an enginebay. After you finish, you'll be shocked how much useless wiring is included in a fox mustang.

Have fun!

[surfsup]

I was going to drop the gas tank and either replace it or just change the pick ups, the duraspark your talking about is that a silver box? I have something mounted on the fire wall driver side that appears to be an ignition module; I don’t see anything behind the battery, I was thinking about going with a MSD set up but not sure which one. This weekend I’m going to rip out all the wiring from the 85 and see what’s what

[crazypete]

MSD AL6 and a blaster coil is what I use but the duraspark (I've never seen one, but the wires should go to the coil so check the wire color. It sounds like it though) is quite good enough. I dont think the MSD will give you really that much of a boost over the duraspark so it's not worth it. Get a bigger coil though, so you can gap the plugs out. A fatter spark WILL help you (and eat rotors and caps but I think you'll find that its worth it)

[surfsup]

Ok I ripped out the entire harness but I can not make head or tails of what the f_ _ _k I did. There has to be an easy way, also this car has a computer, or at lease is looks like one, it was bolted on the pass, side behind the kick pane,l but the serial number says it’s a four barrel, I also ripped out the interior harness. With all the 4 cyl that are changed to 5.0 I can’t believe no one has a web site that has a detailed diagram on this

[tmoss]

There is harness descriptions/layouts and lots of diagrams that might help at:

www.veryuseful.com/mustang/tech/engine

[surfsup]

tmoss thanks I'll check the site out and let you know how things went