5.4 questions

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ams2737

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Hey everyone I'm new to the forum but I have a few questions that it haven't found the answers on. I have a 1997 XLT 4.6 romeo that needs head gaskets replaced but I want to put in a 5.4 PI motor in it. I know it will work but my question is if I get the full engine harness and PCM/ECU will the harness plug in with the other harnesses or do I have to modify it? I don't mind the COP because it's a lot cleaner under the good than the coil packs with plug wires. I hope this question makes sense
 

FordandPolaris

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I'm guessing not everything will match perfectly, but some stuff should. I haven't found a thread detailing that swap yet so if you do it please keep us informed of the progress


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ams2737

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Once I find it I'll let you know. I guess some people use the 4.6 harness etc. But i would like pics of how people did it.
 

IMINYOURCHAIR

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if you have a 4.6 pre 2000 model year, you likely have two coils and eight wires, the 5.4 from MY97' and up all had COP. so, you will need eight of those and the harness to power them. knowing this there may bee a need for a new harness at least. I can't say about the ecu/pcm.

what are you planning on doing as far as the transmission goes? I don't know that the 5.4 came with the weaker 4R70W that the 4.6 was commonly paired with.
 

BIG GREEN FORD

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if you have a 4.6 pre 2000 model year, you likely have two coils and eight wires, the 5.4 from MY97' and up all had COP. so, you will need eight of those and the harness to power them. knowing this there may bee a need for a new harness at least. I can't say about the ecu/pcm.

what are you planning on doing as far as the transmission goes? I don't know that the 5.4 came with the weaker 4R70W that the 4.6 was commonly paired with.

The 5.4 also came with 4R70W
 
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ams2737

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I have the 4r70w transmission. I have read that the 5.4 uses that transmission also so I'm hoping it bolts up.
As for the COP I was hoping if I got the whole engine harness that everything would bolt up and run smoothly which is why I was asking if I needed anything else other than that?
And I have the 4.6 npi motor currently but I was wanting the 5.4 pi motor to swap in my truck
 
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