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Carbed 302 or 351 into an 87 coupe...questions

  • Thread starter Thread starter Matts89LX5.0
  • Start date Start date Aug 9, 2004
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Matts89LX5.0

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#1
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car was orginally a 4 banger, do I need to get a computer to run all the electronic junk or what? My 85 GT hasa computer inside the kick panel, but I always thought a carbed motor did not have an ECU. If I do run either motor in my coupe, and need a computer, which computer do I need??? Thanks in advance.
 

MrKwik

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#2
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I am doing the same thing with my 93 convertible. I removed the computer and about 30lbs of wiring harness from the engine compartment. As far as I could tell the computer doesnt do anything other than control the fuel injection and ignition so if you are going carbed you shouldnt need it at all.
 

dastang2

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there is no replacement for deplacement, go with a 351.
 
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Matts89LX5.0

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wel would my 85 gt have a computer because the distributor is vaccuum advance??? this carb stuff is confusing me right now
 
T

tjm73

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Matts89LX5.0 said:
car was orginally a 4 banger, do I need to get a computer to run all the electronic junk or what? My 85 GT hasa computer inside the kick panel, but I always thought a carbed motor did not have an ECU. If I do run either motor in my coupe, and need a computer, which computer do I need??? Thanks in advance.
Click to expand...


In that car the engine control ECU is only running the engine. In fact, it runs on a seperate wiring harness. Pull the computer that's in it and throw it away. Is the 85 an automatic? They did have a ECU, but not a carb.
 

dastang2

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85's did have carbs they have an ignition module for the duraspark ignition and i believe that is it. unless they had a feedback carb hooked to some 02 sensors and then it probably has a computer
 
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D347643

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#7
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pull the comp and sell it, lol
 
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Matts89LX5.0

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ok lol btw car was originally an auto but previous owner changed that lol
 
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tjm73

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dastang2 said:
85's did have carbs they have an ignition module for the duraspark ignition and i believe that is it. unless they had a feedback carb hooked to some 02 sensors and then it probably has a computer
Click to expand...

In 1985, Mustang's with the V8 and an auto had a computer ECU. They do not have a carb, they have CFI (central fuel injection). In 1985, cars with 5 speeds did not have ECU's because they were carb'd. The Duraspark control unit is located under the hood on those cars, not in the kickpanel. Get your facts straight.
 
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tjm73

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Matts89LX5.0 said:
ok lol btw car was originally an auto but previous owner changed that lol
Click to expand...

Then he didn't bother to pull the ECU when he swapped out the automatic tranny.
 

MrKwik

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tjm73 said:
Then he didn't bother to pull the ECU when he swapped out the automatic tranny.
Click to expand...
If the car was originaly an automatic but someone swapped in a 5 speed, it would still need the ECU to run the CFI. Unless of course he swapped out the CFI for a carb as well. Im pretty sure that there were no carburated automatics in 85.
 

dastang2

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i didn't say anything about the kickpanel, put your glasses on and read better next time
 
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Matts89LX5.0

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originally was a CFI auto, now 5 spd carbed car.
 

fivelitercoupe

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#14
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With the carbed set-up you dont need to run a computer at all, like said before it pretty much just controls the fuel injection a few other lil things, we just put a carbed 302 in a 98 6-cylinder and we completely took the computer out. Of course we have no accesories on the car what so ever but all the electronics in the car still work perfectly fine.....
 
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tjm73

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#15
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dastang2 said:
i didn't say anything about the kickpanel, put your glasses on and read better next time
Click to expand...

Hmmmm....

dastang2 said:
85's did have carbs they have an ignition module for the duraspark ignition and i believe that is it.
Click to expand...

Did you not write this in response to this post?

Matts89LX5.0 said:
My 85 GT hasa computer inside the kick panel, but I always thought a carbed motor did not have an ECU.
Click to expand...

That would indicate to me that you were reffering to this question/statement. And logic dictates that is what you meant. Hope you weren't offended, because I was kidding.
 
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Matts89LX5.0

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uhm...thanks for everyones help on this....anything else I should know about putting a carbed motor into a car that was originally EFI????
 
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tjm73

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#17
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Matts89LX5.0 said:
uhm...thanks for everyones help on this....anything else I should know about putting a carbed motor into a car that was originally EFI????
Click to expand...

Ummmm...only thing I can think of is that 4 cyl cars run their fuel line up the opposite side of the car as the V8 cars. But that shouldn't really matter since you will probably be running your own new high flow fuel line. The 4 cyl fuel line will be quite possibly dangerously close to your exhaust system. So watch out for that.
 
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Matts89LX5.0

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well the car was a 4 cylinder conversion to 5.0 already, but the tranny and motor took a dump, so i got rid of them and found the fuel lines were kinked so i decided to just do everything the way I want it. I set up a car completely for an EFI V8 conversion once before on an 88 4 banger. I just don't know much about carb set ups. Matt
 
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