I am playing a bit of catch up to the rest of you. My X died a few weeks ago.
I also plan on the 5.0 swap. I will be working with a mechanic who does a lot of engine swaps. I was just admiring a TBird 2.3 Turbo he stuffed into an MG - very nice.
After looking at my wire harness (92 X) and several manuals I decided to buy the Harwood maual which is quite helpful.
When Using the Ford Motor Sport (FMS) wire harness you need to use both the main and engine harness and remove the same from the explorer. As mentioned by Sandy.
You will not be keeping your 4.0 engine harness, main harness or computer. Don't even attempt it. The mustang main harness should go through the firewall and mount the mustang computer the same way the X harness worked.
The wires you need to "integrate" into the existing system is to supply power to the 5.0 harness and connect your instuments. The majority of this is accomplished between the two connectors that should be vacant at the moment on the engine harness (On the 93 mustang harness I looked at there was a round and a rectangular connector that were behind the throttle body on the stang. They are each 8 pin connectors.)
You will NOT have these connectors. I would suggest you go to the junk yard and get the mates for the two connectors (females I believe).
You will be connecting from pins on these connectors to your main wire connector block that passes through the fire wall ( I believe it is connector C147 on the X wire diagrams). As an alternative you could trace the proper wires out of the fire wall connector back to the next connector block in the circut and stub in there (this will take a lot of wire tracing).
Sandy's suggestion to put a battery back in to test for the auxillary circuts and most important find those power sources. According to Harwood you only need to find 12Volt source for 1) Crank only and 2) Crank & Run. I agree with Sandy - find a run only power source while you are at it (Harwood's manual is not as clear as it should be about this).
I traced my rear ABS and fuel pump wires and I can't find anything that coonnects them into the main wire harness. I still have to trace the fuel pump cut off wire.
I talked with a person at Ford Motorsport who put a blown 351 in his early explorer (He said if he had it to do over he would go with the 5.0, not the 351). He confirmed that there are only about a dozen connections to be made. Everything else stands on its own. He also stated that he needed to modify the oil pan further when using the Superlift 6" lift kit. This may just be true for the 351.
I will have to look at the earlier posts, but briefly could you tell me what you used for the following:
Whose motor mounts:
Whose Headers:
Engine model/year:
Front Accessory brackets you used:
What accessories did you re-use:
Right now I am debating if I want to use an Explorer V8 as a doner, Or have an engine built.
I plan on using the transmission from a full size Bronco / F-150 (Yes another Mazda - model M5R2. A little stronger than our M5R1). I have had T5's before and they have problems as well, especially with the shifter. The third party shifters help, but the inside mechanism that switches the shift rails is not well designed.
