5.0 transplant

Topic: 5.0 transplant (Read 12756 times) previous topic - next topic

5.0 transplant

December 10, 2004, 09:49:47 AM

I am going to be starting the 5.0 HO transplant into my 85 t-bird 5.0 in about two months. right now I am looking at motor prices and whats available. My cousin is going to be giving me an 88 couger 5.0. It has 200,000 miles on it and doesn't want to sell it to anyone. My question is will the cougar supply me with everything I need. I plan on buying the Painless wire harness. And I will pickup a computer from wherever. I just don't know if I will be able to find a whole mustang to use. I have reviewed the tech section on this on CoolCats and it looks like The cougar would be ok as long as I got the wire harnass and computer, but I wasn't sure. As I look at motors what would it have to come with so Im not out buying a bunch of stuff at the salvage yards. I am basically trying to use the cougar, painless wiriing harnass, mustang 5.0 HO computer, and a mustang 5.0 motor. Also is the AOD tranny on the 88 cougar better than my 85 tbird AOD tranny? The 88 tranny was rebuild about 30,000 miles ago. If it's not I will just look for the transmission off of a stang as well. Thanks for your help, Jason.

Re: 5.0 transplant

Reply #1 – December 10, 2004, 10:19:31 AM

Jasonfischer from the old Fox board? And Cat Jam? If so, welcome back.

Only thing I'm sure on is the tranny. I know the 88+ valve bodies are better, so you'd be at an advantage using the Cougar tranny.

Re: 5.0 transplant

Reply #2 – December 10, 2004, 02:01:38 PM

Yes it is me. I haven't been on in a while, shame on me. I did a demolition derby, then there was a couple of months I was working a lot and then hunting season. I am now switching gears and getting back to my tbird. It's been sitting for a few months so its a good time to do the swap. All I have to do is talk the wife out of her garage space.

Re: 5.0 transplant

Reply #3 – December 10, 2004, 07:40:38 PM

if the cars a 5.0 you dont need a harness (i dont think). the one you have will work fine (im pretty sure. its true for the 87-88s). use a mustang computer (87-88 sd). im doing this in the next 2 weeks or so. im even keeping it speed density to keep things even simpler.

Re: 5.0 transplant

Reply #4 – December 10, 2004, 09:52:19 PM

Quote from: shame302

if the cars a 5.0 you dont need a harness (i dont think). the one you have will work fine (im pretty sure. its true for the 87-88s).

It's also true of the '86, but unfortunatly not on a '85. You're gonna need the later harness....

Re: 5.0 transplant

Reply #5 – December 10, 2004, 11:11:06 PM

So I can use the harness from the 88 cougar? It will plug into the mustang computer? Even if I could I was still thinking of doing the painless wiring just because I figured it would be a lot easier and user friendly. I saw it used on a show and it looked awesome being that everything was labeled and such. What do you guys think? Another question; does the cobra version use the same wiring, computer etc., is it worth paying extra for it?

Re: 5.0 transplant

Reply #6 – December 10, 2004, 11:27:44 PM

yes it will plug into the stang computer (providing the computer is speed density) and you are planning on running speed density.

I think their might be one slight pin adjustment to be made. Maby someone else will jump in here.

Re: 5.0 transplant

Reply #7 – December 11, 2004, 08:44:48 AM

The 88 engine harness will plug into the Mustang computer, but will not plug into the 85 dash harness by the master cylinder. The plugs are different, maybe you could rewire the plugs

. Unless you want to put the 88 dash in. :ies:

Re: 5.0 transplant

Reply #8 – December 11, 2004, 07:19:55 PM

Shoot. Basically what I am hearing is that I picked the hardest model and year to do this swap. Oh well, I like a good challenge. So reqaurdless of what harness i use (painless, cougar or mustang) it's not going to connect to what I've got. What functions are in the harness that needs to go to the plug at the master cylinder? I am very foggy about how the whole thing is going to work. How does the ignition get tied into the new system? (Which harness?) Coolcats says to remove all wiring and hoses so Im guessing that the new engine will contain mostly wiring and less hoses being that my current motor is CFI. Keep the info coming guys, the better picture I have of what to expect the smoother this whole thing will go for me. I am sure I will understand more as I get into it but I would like to know as much as possible before I start on it. Thanks a lot guys.

Re: 5.0 transplant

Reply #9 – December 11, 2004, 08:45:04 PM

You really need EVTM's for both your and the donor car. You'll find that the circuits for both cars are similar, just the plugs are different. You can either repin the '85 into the '88 conectors(providing of course they are of the same gender)then just plug em in. Or you can make a adaptor harness from the '85 engine and the and the '88 body harness connectors(which is what I did when I did my swap).

Re: 5.0 transplant

Reply #10 – December 11, 2004, 11:55:15 PM

Making the adapter harness sounds like a good solution for that problem. Thanks TurboCoupe50.

Re: 5.0 transplant

Reply #11 – December 12, 2004, 06:47:07 AM

Quote from: jasontbird

Making the adapter harness sounds like a good solution for that problem. Thanks TurboCoupe50.

Yea, just cut the plugs off the old engine and body harness', leaving about 6"-8" of wire on each. You probably can match most of the wires up color for color, but likely some circuits will use different colors(EVTM time). To be sure there is no problem down the road, I soldered and shrink wrapped my connections.

The '88 harness will have three plugs, and the one that has only three wires is the one that actally puts the show on the road. The red/green wire in that plug is what powers the coil, EEC, and fuel pump relays. I found with every bit of the engine harness disconnected(except for ground connections and the fuel pump harness of course), as long as the red/green wire is connected, the engine will run.

Re: 5.0 transplant

Reply #12 – December 12, 2004, 09:06:22 AM

So if you have an 88 5.0 car, to use the HO motor all you need is a SD computer, and that just plugs right in without having to change any wires??

Re: 5.0 transplant

Reply #13 – December 12, 2004, 09:32:20 AM

Quote from: 88KSXR7

So if you have an 88 5.0 car, to use the HO motor all you need is a SD computer, and that just plugs right in without having to change any wires??

Yup, the Stang SD computer plugs in to a 5.0 '86-'88 Bird/Coug harness with no modifications necessary. Also a '86-'92 Lincoln LSC HO computer can be used(are all SD), but begnning '88 they have a speed limiter set at 106 mph.

Re: 5.0 transplant

Reply #14 – December 12, 2004, 10:32:18 AM

What are EVTM's. Is that the electrical diagram?