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Topic: CFI to SEFI ver.238412412873412783 (Read 2312 times) previous topic - next topic

CFI to SEFI ver.238412412873412783

Okay, since I've tried searching with no good results, whats the easiest way to swap out CFI for SEFI? Are there differences between a T-bird and Cougar SEFI harness and a 86-89 Mustang EFI harness? Has anyone used the Ford Motorsport EFI harness? Thanks in advance.

CFI to SEFI ver.238412412873412783

Reply #1 –
Quote from: Drewstang;187302
Okay, since I've tried searching with no good results, whats the easiest way to swap out CFI for SEFI? Are there differences between a T-bird and Cougar SEFI harness and a 86-89 Mustang EFI harness? Has anyone used the Ford Motorsport EFI harness? Thanks in advance.

Easiest way would be to find an '87-'88 Bird/Cougar harness, and eec, and other necessary engine parts...OR HO parts and matching eec.

I've not had any experience with the Motorsport harness.
'84 Mustang
'98 Explorer 5.0
'03 Focus, dropped a valve seat. yay. freakin' split port engines...
'06 Explorer EB 4.6

CFI to SEFI ver.238412412873412783

Reply #2 –
I'd like to have Mass Air, and I know this wasn't used on most 86-88 T-birds. I could do the conversion, but I'd like to just drop in the harness and EEC and go. Can someone take a good engine bay pic where the CFI harness meets the dash harness, and where the EEC harness meets the body harness on the pass side kick panel? I think with good pics, I'll be able to tell which harness will work. I've worked with the 89 Mass Air harness and EEC in older Mustangs, and I've also helped convert a few street rods and one turbo 66 Fairlane to SEFI using the FMS harness.

CFI to SEFI ver.238412412873412783

Reply #3 –
The EEC harness will come out on it's own.  Unplug it from the ECU, unbolt the ground wire and push it through and that should be it.
Long live the 4-eyes!  - '83 Tbird Turbo

CFI to SEFI ver.238412412873412783

Reply #4 –
Most people that have used a Mustang EEC harness have run into problems somewhere along the line...having to switch pins, some smaller harnesses are different, etc. The same would probably be true of the Motorsport wiring kit as it's based upon the Mustang harness. If you got a shop manual for the Mustang EEC and also the Cougar/T-Bird EEC, you can easily repin it so that it would work with your car (i.e. turn on the fuel pump). The '89 Mustang mass air harness would theoretically be the one to get (pre-airbag) but just don't ask Vinnietbird about that one. ;)

The only true "plug-and-play" solution is the 1986-88 Cougar/T-Bird 5.0 harness, preferably from your particular model year. This gets you SEFI and speed density. From there you can purchase a small 4-wire mass air hookup kit for around $30 US and attach that to the new SEFI harness. Very simple, efficient, really not much in the way of swapping wires (you will have to for mass air but it's only two, plus piggyback two wires, nothing scary). For that matter you could mate the mass air wiring in with the Cougar/T-Bird 5.0 wiring outside of the car, install it, and then you don't have to worry about running a separate harness. Just be careful, as another member here had an issue with doing that, and the engine didn't run right...it was tracked down to the wiring, although we felt is was simply a bad harness to begin with.

Also be aware that the actual shape of the holes where the EEC harness comes through seems to be different, depending on the harness and model year. Some are rectangular, some are oval. You may have to massage some metal.

CFI to SEFI ver.238412412873412783

Reply #5 –
Quote from: Chuck W;187392
The EEC harness will come out on it's own.  Unplug it from the ECU, unbolt the ground wire and push it through and that should be it.


Thanks EFI bot. That didn't answer the original question did it?



I'm asking which harness to use to switch to SEFI, not how to get the old one out.



Eric- Thanks for the info. I guess I need to find a 86 SEFI harness. If anyone happens to have one, please let me know.

CFI to SEFI ver.238412412873412783

Reply #6 –
Quote from: Drewstang;187403
Thanks EFI bot. That didn't answer the original question did it?



You're welcome smartass bot.
Long live the 4-eyes!  - '83 Tbird Turbo

CFI to SEFI ver.238412412873412783

Reply #8 –
Nevermind, you're not worth my time.
Long live the 4-eyes!  - '83 Tbird Turbo

CFI to SEFI ver.238412412873412783

Reply #10 –
hey bluegrass,, why you messin with chuck, hes a good guy.  You do need to know that no,, none noda,, no a single tbird/coug from the years you indicated came with MAF.  Just fyi. 

Eric is dead on and for all your upgrades, try like heck to stick with the wirng that came in these cars.  This will reduce the future complications especially when it comes time for the full electronic cluster.


yours truely, former area code 606 resident.

CFI to SEFI ver.238412412873412783

Reply #12 –
Ok guys this is the end all to this question....

86 sefi harness..... 

83, 84 and 85  v8 cars used the same connector for the dash interface as the 86.  In 87 ford was switching to weatherproof connectors.

This is not to say that the 86 harness will drop in.. But it is by far the easiest harness to use.
One 88

CFI to SEFI ver.238412412873412783

Reply #14 –
Hello

  One thing to remember is to match your cam to your computer.

mustang computers need a H.O. cam.  T-bird/cougar computers need a  S.O. cam.  They have different firing orders.  Mixing cams will confuse the computer.  A bit off topic but good to know.  I have been there and it causes a lot of headaches.

igiveup
86 ELAN t-bird all mustang parts (Sold)  I love this site.
85 bronco 2. Dura sparked (soon TBI) too many parts
1988 5.0 lx Stang (93 gt cobra mass air)
85 Honda 250sx trike
06 F150 tow rig. all kinds of goodies.(This is why I sold the Bird)
igiveup was the only name I could get. lol