Engine Will it fit/work

Randy1985

Member
Jul 10, 2022
8
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Cochran ga
Ok Guys first off hey to everyone and thanks for all the advice in advance. So I have a 1985 foxbody carb’d I want to go to a EFI system. My question is will the EFI system and computer out of a explorer or a F150 work. I’m on a very low budget and used mustang parts are hard to find in middle Ga.
 
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I agree with mike (as usual) you likely need to use the dash and under hood wiring from an 86.
You may look into an aftermarket efi.
Now there is nothing wrong with a carb 'd setup, been done for ever with great success. And yours being an 85 it's a lot less money and hassele.
 
You’ll need a complete engine/ECU harness from a 86+ mustang and wiring diagrams. Harder to find and not cheap.


Or you go aftermarket ECU like a terminator X and then factor in tuning costs.
 
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So I should just leave the street demon carb on it
I still have carbureted and EFI cars. Except when it’s been parked for months, my V-8, Holley equipped car starts as fast or faster than the EFI cars and runs quite well. Any increase in MPG would never pay for the EFI upgrade and learning curve of an aftermarket system. But I have a Holley tuning book or two and grew up working with the tech.
A Demon is a fancy Holley. There is more to the story, but it also applies to QFT. They are all extremely tuneable and are not very complicated.
I suspect if there is a driveability problem, it will still need chased down with an aftermarket EFI system.
So to help with your budget, what is going on that you are unhappy with?
 
Well the response. I have owned several of the fox bodies just not carb’d. can I run the VIN number somewhere to tell if it was ever Fuel injection?
You did not answer the question.. Why are you dead set against using a carb which is what this car came with new if it was a V8 car?
 
Well the response. I have owned several of the fox bodies just not carb’d. can I run the VIN number somewhere to tell if it was ever Fuel injection?
your gonna have to describe the response issue better, slow acceleration, off idle stumble, bog?
I think the V6 got CFI but the V8 got a carb in 85, I know the GT model has a carb in 85. Someone (@FoxChasis ?) will correct me.
 
Unless you plan on doing tons of mods to the car something like a Holly Sniper EFI might do the trick for you. It would sure be easier and cheaper than trying to install a stock EFI setup on it.
 
your gonna have to describe the response issue better, slow acceleration, off idle stumble, bog?
I think the V6 got CFI but the V8 got a carb in 85, I know the GT model has a carb in 85. Someone (@FoxChasis ?) will correct me.
5.0L GT in 84 and 85 had carb or CFI

carb came with manual trans
CFI came with auto trans

No VIN decoder that is actually worth a damn is going to tell you which it is. Some VIN decoders claim the CFI engine is VIN code F. Wrong. Both engines are code M. The CFI 5.0L engine in 1984-85 Capri/Mustang/LTD/Marquis is the H.O. version, i.e. code M, not the S.O. version in Continental/Cougar/Thunderbird/Mark VII, i.e. code F. Before 1984 code F was the H.O. engine in Capri/Mustang.
 
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Well the response. I have owned several of the fox bodies just not carb’d. can I run the VIN number somewhere to tell if it was ever Fuel injection?
So what do you mean by the response? Does it stumble when you tip in, when off the line, does it bog at full throttle? Is there a certain RPM it runs poorly at?
Does it not answer your questions politely or ignore you? (That last one is more likely from a black Pontiac named KITT or a computer named HAL, but I had to ask.)
 
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