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Topic: 3.8 - 5.0 swapout (Read 3039 times) previous topic - next topic

3.8 - 5.0 swapout

I just recently bought a 1989 Mustang LX with a 5.0. I plan to use it for my 1986 T-Bird with a 3.8. I was told I could use the front end out of the LX to achieve an upgrade for the Bird. Has anyone had any experience with this swap? This is my first Ford venture. I have previously been a "Chevy Man". I look forward to this work, as the T-Bird is an awesome car. Its just been sitting in my garage for years now, awaiting some care. The 3.8 quit running some time back due to some electrical problems. I can't wait to get the swap done and get it on the road again. Hopefully, some of you guys can steer me away from potential problems I might encounter along the way. I look forward to your responses and thanks to all who help.

3.8 - 5.0 swapout

Reply #1 –
check out coolcats.net in the tech section. It'll tell you all. Any questions come right on back and ask
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

3.8 - 5.0 swapout

Reply #2 –
You'll need to swap the fuel lines,fuel pump,exhaust,and you'll need a wiring harness.The Mustang and T-Birds have different harnesses.I found that out this summer.You'll also need the Mustang computer.Do the Mass Air conversion while your at it (do it and get it over with).I can speak for myself and say that you need a 5.0 T-Bird or Cougar harness.You can swap the front suspension to the Bird for larger brakes,and I'd also swap the rear end from the Bird and use the Stang rear.better gears and it should be a Locker,although,I have seen a few stangs that didn't have a locker.Good luck.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

3.8 - 5.0 swapout

Reply #3 –
Quote from: vinnietbird;193025
The Mustang and T-Birds have different harnesses.I found that out this summer.You'll also need the Mustang computer.Do the Mass Air conversion while your at it.



The '89 Stangs ARE Mass AIR... Harness can be used, just will take a bit of adapting... I made adapter harnesses from the original 2.3 engine & 5.0 body connectors... Also possible to re-pin the the harness so it will plug in without making adapters...

Basically if you are electrically challenged, it will be a tough swap... If you're good with wiring or have a buddy who is... Piece O cake...

3.8 - 5.0 swapout

Reply #4 –
I had a Stang harness and it had a couple of different plugs than my Sport's harness,so,I sold the satng harness,and bought the conversion kit for Mass Air.I know the '89 is a Mass Air car,I meant do the swap on the Bird.I've seen a lot of folks who keep the speed density,which,there is nothing wrong with.I didn't want to do a lot of work on converting the harness because I hate doing that kind of electrical work.Foglights,stereo,no problem.My computer harness,that makes me nervous.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

3.8 - 5.0 swapout

Reply #5 –
You'll also need V8 mounts/brackets for a Cougar/Tbird, as the Stang mounts won't work. On the '86-88 K-member there seems to be a bit of confusion on the mounts, which ARE available at better parts stores, versus the brackets, which are NOT available from any parts store.
However, ChuckW has saved our bacon with his custom mounts.
Or you can look for those rare brackets in junkyards, too, although the yards I've looked in, the brackets are always gone from those cars, usually the first thing taken, I think.

Good luck, and this is the place to come to about Fox Tbird/Cougars!
'84 Mustang
'98 Explorer 5.0
'03 Focus, dropped a valve seat. yay. freakin' split port engines...
'06 Explorer EB 4.6

3.8 - 5.0 swapout

Reply #6 –
I just happen to have a set of those rare brackets,although one would have to go to the parts store for new insulators.They don't cost too much.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

3.8 - 5.0 swapout

Reply #7 –
It's about time someone used a stang as a doner for a bird instead of the other way around!

3.8 - 5.0 swapout

Reply #8 –
Hopefully, I'll get this project started after the first of the new year, I have to get some working room in the garage. I'll make sure to dospoogeent with pics and try to post as progress is made. Look forward to all your helpful hints and comments throughout the entire job.

3.8 - 5.0 swapout

Reply #9 –
The v6 engine mounts should be the same as the 5.0's.
But being old should be replaced anyway.
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

3.8 - 5.0 swapout

Reply #10 –
Turbocoupe50, what kind of adapters did you have to make? Re-pinning the harness, you wouldn't have a listing of needed changes would you? I haven't yet started this, just trying to get all ducks in a row to save time and trouble.......

3.8 - 5.0 swapout

Reply #11 –
No real notes, did it back in '99... The '87-'88 TCs are unique and not like any other Bird/Coug, many of my changes would not apply to your swap... My 5.0 harness came from a '87 Tbird(had a parts car), converted it to mass air prior to installing it...

Mostly it's matching colors, Stang and Bird  color codes are generally the same... A few are sometimes different, as occasionally similar colors are substituted when the harness is manufactured... Mainly your going to find each year the harness' are revised and probably different from prev years... Have no experience with any year 3.8(that isn't General Motors)...

I have done it!

Reply #12 –
If you have any Qustions just ask! I had an 84 cougar with 3.8 swaped with the 302 and now 351w

3.8 - 5.0 swapout

Reply #13 –
What year 302? Mustang donor? How about wiring issues?

3.8 - 5.0 swapout

Reply #14 –
You could always just swap k member instead of getting "ultra rare" brackets...

Get a 86-88 5.0 harness from a tbird or cougar and your set...
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com