LS Swap help needed?

1998 FORD MUSTANG

160,000 MILES • 3.8L • V6 • 2WD • MANUAL

BRENNANREEVE99

MEMBER
1 POST

I just watched a video on YouTube for a really good LS swap wiring tutorial. My question is on the electrical harness. Would I still be able to follow the LS to ECM procedure on the video or would it be different in my case? If different, what electrical parts would I need to complete the job? This is my first engine swap I am taking on and terrified to get into the wiring aspect.

Sep 10, 2024 at 6:43 AM

STEVE W.

✓ASE Certified Mechanic
15,200 POSTS

If you are swapping an LS for the Mustang your best bet would be to get a stand-alone controller instead of trying to use the factory parts but be aware if you are in any state that does emissions testing it would likely fail. You are also looking at a different K member up front and altering the spring mounting to get the LS to tuck in that engine bay.

Sep 10, 2024 at 12:25 PM

RYAN L

✓ASE Certified Mechanic
272 POSTS

Hey there!

So, I would definitely have a stand-alone system like I did with the Bel Air. None of the stock Ford gauges will work, except for maybe the speedometer and fuel gauge. All of that will have to be modified or replaced.

Essentially, I would run two ECMs on the same car. One to power and control all of the Ford stuff, fuel gauge and lights. Then the second one that just handles the LS engine.

Hope that helps!

Best,
Ryan

Sep 11, 2024 at 10:47 AM

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