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Topic: 86 T-Bird CFI questions... (Read 1021 times) previous topic - next topic

86 T-Bird CFI questions...

Hi, I'm looking at buying an 86 T-Bird 5.0. It has the CFI system in it, I was wondering if you were to put the MPFI system in, would you have to replace your entire wiring harness? I know the 5.0 Mustangs you have to change the dash to convert it, well, you don't have to, just there's a million wires that run through the dash and it's all one piece, because I did that to my Mustang. So what I'm asking is how involved do I have to get?

Also want to convert it to H.O. since I have a spare cam and set of heads from my Mustang after modding it. If I don't convert to MPFI will I encounter any running problems due to the different firing order? Or is the CFI actually decent enough and worth keeping? Aswell, how would the flat-top pistons react to the E7TE heads? Would there be any problems there? (detonation mainly, or would it lower compression compared to the forger or hyperneumic pistons of the Mustang?)

Oh yah, and will Mustang headers fit the chassis because I have a 2 spare sets, one flowtech and the other stock

I wanna get some power out of that weiner 5.0, can't believe Ford did that to them. A 5 litre with 155hp, that's just embarassing.

Any help would be greatly appreciated, thanks in advance.

86 T-Bird CFI questions...

Reply #1
a 1986 is sefi, so it is prolly a diffrent year. THe e7's and headers bolt up fine. there isnt alot that is readily availible as far as cfi goes. they ditched it for a reason. Are you sure it is not sefi?

5.0's were CFI 83-85 I do belive. 86-88 were sefi. Also, the 86-87 only has 150hp, not 155. 88 got duels for the v-8 only.

tell us for sure it is a 86 or not.
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

86 T-Bird CFI questions...

Reply #2
I am positive it is an 86, looked at the tag on the door and the vin

86 T-Bird CFI questions...

Reply #3
Now are you posotive it is a 5.0?
One 88

86 T-Bird CFI questions...

Reply #4
Liquid_02, are you the guy from mustangforums.com?

You have to keep in mind, canadian cars got different equipment than the american cars. You could get a carb all the way up untill 87, when they were only available on 83's in the states, so who knows how it goes as far as CFI.

If you can find yourself an SEFI 5.0 wiring harness from an 86 tbird, it should all be plug and play. Converting to HO would be as simple as (depending on your skill) the cam, heads, intake manifold and mustang EEC.

As for headers, both sets of your mustang headers will fit

You could probably keep the CFI with an HO cam, but you would have to adjust your firing order on the spark plug wires as far as i know, ive never seen that conversion done, but it could probably work. The CFI would choke out the power potential with the quickness though.
It's Gumby's fault.

86 T-Bird CFI questions...

Reply #5
Ford totally abondoned CFI on the 5.0 begnning '86(P/Us & vans got EFI mid year 85). In the Ford Shop manuals and EVTM there are only SEFI 5.0s for '86 and that includes Canada. If the VIN says it's a '86 then so be it, but I'd suspect someone has swapped VIN tag to a '85(does it have the high mount stop lamp??? Manditory begnning '86). As already mentioned you sure its a 5.0??? Suppose someone could have swapped in a CFI engine but it's doubtfull. Anyway if it is a CFI engine then it should have the E5AE or E5TE heads which are basically the same as E7TEs. The E6s were only used on '86 HOs and all SEFI Birds/Cougs. What reach plugs does it have?? E6 uses 3/4 reach while E5 & 7s use the 1/2" reach.

The Canadian V6s were carbed(not CFI) through '86, with the '87 being CFI like its american counterpart. BTW ALL American/Canadian Birds/Cougs were built in Lorain OH, so it wasn't like maybe this plant built this and that plant built something different.

86 T-Bird CFI questions...

Reply #6
Yes I am the same guy from MustangForums sir TBird.

I am positive it is a 5.0, I looked right at the engine, it was a V8 (Only V8 available was the 5.0) and it had it stamped on the air cleaner. Don't take me for a dumbass aha, I've worked in a auto repair shop since I was 15. Only reason I'm asking about the H.O. part is that, Im changing all the necessary components, (cam's already done and heads are on back-order) minus intake since they're different,  in my Mustang so I could simply put them on the T-Bird.

The car does have high mounts I believe, but you have to remember, you don't need high mounts in Canada.

Does the engine harness disconnect just inside the firewall, or does it run through the dash? because if it runs through the dash I CBF to change that.

What do you mean by "reach plugs"? Length of the thread? Never the less, I haven't taken them out, when I take a better look at the car I will be because I will be doing a compression test anyway.

Oh yah, if I don't change the firing order (cam) will it be able to support the new power of the engine?

86 T-Bird CFI questions...

Reply #7
The wiring runs through the firewall, and into the passanger side kickpanel where the EEC is. Thats slightlymisleading, but if you pull the kickpanel, and drop the EEC, thats where the main plug is. There are a few other connectors, but its not terribly hard to find. Youll have a hell of a time getting the harness out though.

By reach plugs, he means the length from the hex area where the socket grips.
It's Gumby's fault.

86 T-Bird CFI questions...

Reply #8
OK whatever year it is, it's CFI. From what I've seen NO SEFI harness will directly mate with a CFI setup. Only plug and play I'm aware of is the '88 EFI V6 which the 5.0 SEFI engine harness will plug directly into...

86 T-Bird CFI questions...

Reply #9
My 87 CFI harness and 87 SEFI harness match up at the firewall plugs. I believe its a matter of getting the same year for the engine harness.
It's Gumby's fault.

86 T-Bird CFI questions...

Reply #10
Quote from: Tbird232ci
My 87 CFI harness and 87 SEFI harness match up at the firewall plugs. I believe its a matter of getting the same year for the engine harness.

UMMMM OK...

86 T-Bird CFI questions...

Reply #11
Will the injector suppor the extra 75hp from an HO? How about the throttle body and intake? will they need to be changed to allow more air-flow for the H.O. or are they the same on the CFI cars?

86 T-Bird CFI questions...

Reply #12
I'll say no...

But there was a CFI HO 5.0 in the '84-'85 Stangs(automatic only), and the same year LSC lincolns. With the Tbody, injectors, EEC and maybe cam you would have the equivilent(175-180hp if I remember correctly). With headres and a clean exaust system it should be in the 200hp range.

86 T-Bird CFI questions...

Reply #13
Quote
My 87 CFI harness and 87 SEFI harness match up at the firewall plugs. I believe its a matter of getting the same year for the engine harness.
And then hoping you have enough wires. CFI only had 2 injectors, so only 2 injector wires. SEFI has 8. Plus different sensors, actuators, vacuum solenoids, etc. Didn't we all chat about this a few months back?
Death awaits you all with nasty, big, pointy teeth.

1988 5.0 Bird, mostly stock, partly not, now gone to T-Bird heaven.
1990 Volvo 740GL. 114 tire-shredding horsies, baby!