88 Mustang 5.0HO Swap into 94 B3000 Help!

grochala · Oct 25, 2015

I have been reading up on this swap and it appears that I have 99% of what I need to finish it off. However after ready as many posts, threads and How To's I'm still not clear of the best way to remove my old wiring and install the 5.0 wiring and computer? Do I literally cut everything off the round firewall plug and splice into that or is that overkill?

No one has been clear on this in any of the how to's I've found. So I'm anxious to start lopping off wiring if it's going to cause me heartburn. Some people say only 5-7 wires need spliced to make it all work right. I have all the diagrams to match everything up but not clear as to what is really necessary.

dangerranger83 · Oct 25, 2015

Power for the ignition coil, starter and anything else to run the 5.0 is all you have to save.

Elutheros · Oct 28, 2015

Since your lights and a lot of other useful stuff are routed through the round plug on the driver side firewall, it would be a bad idea to cut all that off. Start by unplugging the old ECU and tracing those wires out to the engine. Remove the wires that go to the engine controls since the 5.0 harness will have all of those with it. My memory is a little fuzzy on all that I removed, but you can figure a lot of it out as you begin to install the 5.0 harness. Mine had a fire prior to the swap, so I lost a lot of the old harness before I started.

grochala · Oct 28, 2015

Thank you

I have been going over the build threads with a fine tooth comb and gathering all of the necessary tips for the project. There is a lot of great info and I feel good about having it pretty well in order. Just a little anxious about the wiring. Thank you for the suggestions. I plan to split the Mazda wire loom open and separate the Engine harness away from the lighting and other necessary harnesses. Then do the same with the Mustang loom. I expect the few needed connections to splice into the round connector will become quite obvious at that point. So referencing back to the wiring diagrams at that point will help me connect the right wires.

Luckily i found a motor from a Conv Mustang so even the motor mounts are right. The only problem i have is the BBK Even length headers don't look like they are going to work on the drivers side so I'm searching for some stock cast iron manifolds. Might do a little port matching and die grinding to help them flow better.

I plan to take plenty of pics during the process to document the build and will put together a helpful build diary.

dangerranger83 · Oct 28, 2015

My only obstacle was hooking in the 5.0 alternator wiring into the rangers. Thankfully my dad is genius at doing such things, he use to do wiring like that for a living, so it was a cake walk for him. Mine was an external voltage regulator and now I have an internal.

bobbywalter · Oct 29, 2015

which headers?

88 Mustang 5.0HO Swap into 94 B3000 Help!

grochala

New Member

dangerranger83

5.0 HO under the hood!!!

Elutheros

Active Member

grochala

New Member

dangerranger83

5.0 HO under the hood!!!

bobbywalter

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