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Author Topic: Engine wiring harness differences  (Read 14601 times)

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MikeMac

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Engine wiring harness differences
« on: February 08, 2020, 10:08:01 pm »
Can a 4 cylinder engine harness be adapted to a V6 relatively easily? Maybe extending a few wires or totally different?

GTRS Fiero

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Re: Engine wiring harness differences
« Reply #1 on: February 08, 2020, 10:27:06 pm »
What year 4-cylinder?  '85-'86?

MikeMac

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Re: Engine wiring harness differences
« Reply #2 on: February 08, 2020, 10:36:04 pm »
1987 Duke into a 1988 that is currently a Series 1 supercharged but was originally a 4 cylinder. Looking to possibly go to the 2.8/3.4

GTRS Fiero

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Re: Engine wiring harness differences
« Reply #3 on: February 08, 2020, 10:38:48 pm »
Going to use DIS on the new engine?

MikeMac

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Re: Engine wiring harness differences
« Reply #4 on: February 08, 2020, 10:39:53 pm »
1987 Duke into a 1988 that is currently a Series 1 supercharged but was originally a 4 cylinder. Looking to possibly go to the 2.8/3.4

I believe the original 4 cylinder harness was what was modified to the 3800 if my memory serves right. I have the conversion manual somewhere around here. It was a kit from ACE in Texas

MikeMac

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Re: Engine wiring harness differences
« Reply #5 on: February 08, 2020, 10:40:42 pm »
Going to use DIS on the new engine?
eventually, but would go with a distributor at first.

scottb

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Re: Engine wiring harness differences
« Reply #6 on: February 09, 2020, 08:08:30 am »
I might be wrong on this, but I believe that both 87 and 88 2,5s were DIS

TopNotch

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Re: Engine wiring harness differences
« Reply #7 on: February 09, 2020, 08:30:12 am »
I might be wrong on this, but I believe that both 87 and 88 2,5s were DIS
Correct.
The more complex the mind, the greater the need for the simplicity of play.

GTRS Fiero

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Re: Engine wiring harness differences
« Reply #8 on: February 09, 2020, 08:35:03 am »
Which is why I asked, '85-'86.  It would seem to be easier to stick with DIS.

Raydar

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Re: Engine wiring harness differences
« Reply #9 on: February 09, 2020, 09:04:58 am »
I don't know anything about the early Duke harness, but considering the amount of research and fabrication required, I would probably be inclined to just source a V6 harness. I have done a Duke to V6 swap in an 88 coupe. With the proper harness, it's completely plug n play. (Unless ACE modified your wiring inside the car.)
« Last Edit: February 09, 2020, 09:07:28 am by Raydar »
...

TopNotch

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Re: Engine wiring harness differences
« Reply #10 on: February 09, 2020, 09:11:24 am »
BTW, i have an 85 V6 harness. If anyone wants it, you're welcome to it. I understand there are minor differences between 85 and later harnesses, such as how the trunk light is wired.
The more complex the mind, the greater the need for the simplicity of play.

Raydar

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Re: Engine wiring harness differences
« Reply #11 on: February 09, 2020, 09:22:38 am »
BTW, i have an 85 V6 harness. If anyone wants it, you're welcome to it. I understand there are minor differences between 85 and later harnesses, such as how the trunk light is wired.

Is the 85 trunk light part of the engine harness? In the later cars, it's part of the tail light harness.
If it's a manual harness, it will be missing the reverse light wiring, since the switch for the 4 speed was on the shifter.
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MikeMac

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Re: Engine wiring harness differences
« Reply #12 on: February 11, 2020, 11:51:02 am »
BTW, i have an 85 V6 harness. If anyone wants it, you're welcome to it. I understand there are minor differences between 85 and later harnesses, such as how the trunk light is wired.

I would take that harness from you. Thanks Pat

Fierofool

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Re: Engine wiring harness differences
« Reply #13 on: February 11, 2020, 12:15:07 pm »
The 85 trunk light harness runs underneath the left rear fender and is probably a part of the tail light harness.  The switch wiring for the trunk light comes through the side fenderwell from that harness. 
There are three kinds of men:

1.    The ones that learn by reading.
2.    The few who learn by observation.
3.    The rest of them have to pee on the electric fence and find out for themselves.    Will Rogers