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HELP! I have a '87 mustang that came with a 3.2l 4 cylinder. I have a beatiful 5.0 just waiting to drop in. The problem is, how do you wire around the computer to go from fuel injected to a carborated system? With the different voltages, are there other wiring problems that I need to be aware of? Any help would be appreciated.
 

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Should be simple! The only wiring for the engine will be for the coil and oil pressure switch. You can re-use the 4 cyl. coil, it's the same as the V8 version.

do not re-use the 4 cyl trans. Get a V8 version. If using a T5, look for a 90 and later unit. it would also be advisable to install V8 front spindles and brakes along with rear axle.

The earlier Mustangs up to and incluing used the 4 cyl axle and brakes in the V8 models. the 7.5" 4 cyl rear axle will hold up fine on the street as long as you're not dumping the clutch all the time. I use to own an 85 5.0, 5 spd LX that held up just fine with the small axle...including some drag racing.

BTW, we normally don't go past '73 Mustangs here.
 

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As husky said, it should be easy.
I would think converting to a carbed v8 would mean no computer since the computer controls sensors mostly on the intake and ignition. If you are adding MSD you just need to run power to the box and hook up the coil. 12v to the choke and you are done.

Keep in mind I've never done any of this, so I may be wrong. The computer may be involved, but logically I can't think of anything else it would control that you are using.
 

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Depending on where u live it may not be legal to put an older engine setup ie. carb in a newer car.. If the car came efi then u can't go back to a carb and stay complient..
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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The ignition is pretty simple. All you need is a 70's Duraspark setup, distributor, coil, ignition box, and small harness connecting them. (You can use the newer style coil, but this way is very straightforward to get started) Then connect the red wire from the Duraspark box to a wire that is "hot" when the key is on. There are some good diagrams out there for converting older Mustangs to Duraspark. You can apply same info to your conversion (I did). The gauges and alternator wiring are separate fron the EFI stuff. SWMBO's 86 "5.0" still has the 2.3 computer under the dash, not connected to anything in particular I guess. It doesn't effect the function of the car.
One problem you have that I didn't is that you have a fuel pump in the tank. I believe you may be able to use an 86 or earlier non-EFI sending unit instead. Or you may be able to just remove the pump and modify the unit itself to make it a simple pickup. If you wish to retain to "dual" fuel lines, you can use an 85 GT fuel pump. It has a fitting for pressure and one for return.
There are lots more details and issues to be covered and, yes, you will likely be better served by asking questions on other boards that are more oriented to "late-model" Mustangs. (An 1983 GT is 20 years old, is that really "late-model"? ::) OK, Fox -body Mustangs.
 
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