3.8 to 5.0 swap

Topic: 3.8 to 5.0 swap (Read 1891 times) previous topic - next topic

3.8 to 5.0 swap

December 15, 2009, 09:23:22 PM

I have an 87 T-bird LX w/a CFI V6,I was wondering about using a wiring harness from an 88 w/a V6? Since the FI unit was different that year,would I be able to use the main harness w/a 5.0HO? would all of the sensors,connectors ect be where I would need them?

I know the computor and engine harness are obviously different,I have access to one already out of the car if it would work ok,I don't have a V8 car to compare it with tho.

3.8 to 5.0 swap

Reply #1 – December 15, 2009, 10:06:53 PM

Get a harness and all you need from a 5.0 '88 Cougar or Bird.You will need fuel lines,the harnesses,engine (duh) possibly the tranny cross member,motor mounts,computer.The V-8 harness will work with a speed density H.O engine with the right computer,injectors,and H.O cam. There are some more little details,but this is the gist of it.

3.8 to 5.0 swap

Reply #2 – December 15, 2009, 11:02:24 PM

Defiantly NOT from a '88, same year should work, 5.0 harnesses are different between '87 & '88... Either could be made to work but plugs are a bit different...

3.8 to 5.0 swap

Reply #3 – December 15, 2009, 11:07:08 PM

Thank you again vinniebird,

Got the engine and engine harness,the computer and tranny. will the main harness work from the firewall forward? will the V6 connections meet the V8 engine harness?

The engine is still SD will convert to mas air sometime,have P heads port matched to the lower Explorer intake 65mm TB,stock HO injectors and a stock cam,was thinking 1.7 rockers ect?

I have access to that V8 Cougar for small stuff ect,wish the harness was intact,was butchered a bit around the fuse link area.

God bless

3.8 to 5.0 swap

Reply #4 – December 15, 2009, 11:10:58 PM

Thanks TruboCoupe50,

Will the 87 5.0 engine harness match up to the CFI V6 main harness?

3.8 to 5.0 swap

Reply #5 – December 16, 2009, 03:53:54 AM

It should if both are '87.

If the donor car is the same year as yours, it's all systems go, wing commander.

Since it's an '87 3.8 though, you'll for sure need every inch of the fuel lines from the v8, as well as sending unit, pump etc.

I've never messed with an '87 v6 cars, but I'd imagine the lower pressure fuel system is different than the efi systems.

But basically, yes, if the v8 harness you have is the same year as your car, it will interface right into your body harness.

I'd recommend an EVTM as well, it WILL save your ass

It may seem daunting, but as long as you have all the parts you need from the other car, you're set. Just take pictures of the v8 wiring before you pull it out, if you can. It helps with laying it back in later, especially if you're like me, and have 10 things going on at the same time, and take 3 weeks to merely swap the harness itself, lol

keep us posted and take a LOT of pics