Author Topic: Boss 302 unusual wiring  (Read 1951 times)

Offline midlife

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Boss 302 unusual wiring
« on: October 13, 2021, 10:55:39 PM »
I had someone call me today about missing bullet connectors on the gang of plugs past the firewall.  One of them was a green wire, which I have run across before some time ago. 

Now I know Bosses didn't come with A/C, but some (all???) came with A/C wiring but with a twist.  The large female bullet connector out in the engine compartment didn't go to one of the AC switches, but was factory spliced into the ignition RUN-only wire.  The rest of the AC wiring was simply ignored and not hooked up to anything.
My question is this: what was this wire used for?  It was a green wire with a green large female molded plug.  I know it wasn't used for the carb anti-stall line (that's a blue wire with a white plug), nor for a rev limiter.  Was it for an electric choke, perhaps?
Thanks in advance.
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Offline hopey

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Re: Boss 302 unusual wiring
« Reply #1 on: October 17, 2021, 10:32:59 PM »
Not sure about the green plug, but all BOSS 302s were manual chokes, so it wasn?t for that.
1970 BOSS 302
Built 11/15/69 Dearborn

Offline J_Speegle

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Re: Boss 302 unusual wiring
« Reply #2 on: October 17, 2021, 10:49:43 PM »
Period Ford products of the time didn't use electrical chokes.

As for the green female plug. Guessing form the description its visible inside the engine compartment. Will see if it shows up in any of my pictures
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Offline midlife

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Re: Boss 302 unusual wiring
« Reply #3 on: October 17, 2021, 11:51:00 PM »
This unusual green plug could be in 1969/70 Shelby's (I'd have to check my notes as I was going by memory), but the customer was adamant that his 1970 B2 did NOT have AC.  That makes me suspicious that his harness may not be original.  There would be no good reason for the factory to install an AC configured harness in a car that didn't have AC, as the heater box connections are different lengths due to AC and non-AC heater box configurations.
The customer asked specifically for the bullet connector for a green wire, which I explained to him was for AC.  At that point, he said he didn't have AC.  That's when I glommed onto the unusual use for the AC wiring hooked up to the RUN-only wire, which was either in the BOSS or Shelby series.


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Offline J_Speegle

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Re: Boss 302 unusual wiring
« Reply #4 on: October 18, 2021, 04:41:31 AM »
This unusual green plug could be in 1969/70 Shelby's (I'd have to check my notes as I was going by memory),.....................

So your reporting that the "green plug" is found in 69 wiring looms also?

First few 70's I pulled up has a bright green wire but no green boot yet
Jeff Speegle

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Offline Coralsnake

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Re: Boss 302 unusual wiring
« Reply #5 on: October 18, 2021, 10:19:04 AM »
I believe the trend was to make more multi-use harnesses over the years. By 1969, there was no separate "air conditioning" harness. By 1969 all the main, under dash harnesses had the ac leads regardless of the options on the car.

Offline RoyceP

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Re: Boss 302 unusual wiring
« Reply #6 on: October 18, 2021, 11:25:24 AM »

That statement is true for 1968 as well. The 1968 cars with A/C have unused wiring for the non - A/C heater blower motor. The opposite is true if the car has the heater / defroster with no A/C.



I believe the trend was to make more multi-use harnesses over the years. By 1969, there was no separate "air conditioning" harness. By 1969 all the main, under dash harnesses had the ac leads regardless of the options on the car.
1968 W code 427 Cougar XR-7 GTE Feb 23 Dearborn C6 / 3.50 open
1968 R code 428CJ Cougar XR-7 May 13 Dearborn C6 / 3.91 T - Lock

Offline midlife

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Re: Boss 302 unusual wiring
« Reply #7 on: October 18, 2021, 11:29:44 AM »
So your reporting that the "green plug" is found in 69 wiring looms also?

First few 70's I pulled up has a bright green wire but no green boot yet
I wasn't entirely clear.  If it was a Shelby that had the unusual AC wiring (and not a Boss), then the 69 wiring is identical to the 70.  What the customer described was a true 70 wiring harness with the unique blue wire with white plug.
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Offline midlife

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Re: Boss 302 unusual wiring
« Reply #8 on: October 18, 2021, 11:31:47 AM »
I believe the trend was to make more multi-use harnesses over the years. By 1969, there was no separate "air conditioning" harness. By 1969 all the main, under dash harnesses had the ac leads regardless of the options on the car.
I hate to disagree with you, but it wasn't until 1972 that AC wiring became standard in Mustang underdash harnesses.  I have multiple examples of 69, 70 and 71 underdash harnesses without AC wiring.  In 1969, however, the AC wiring was integrated into the underdash harness; perhaps that was what you meant. 
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Offline J_Speegle

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Re: Boss 302 unusual wiring
« Reply #9 on: October 18, 2021, 05:52:17 PM »
Looked through my pictures of 70's (both Boss and neutral) as well as 69 Shelby's and could not come up with a green female boot in any of my pictures connected to wires coming out of that lower center hole where the neutral safety and other plugs is grouped.

If its a really dark green boot guess the real dirty ones may look black but have some originals that are not dirty - have been cleaned.

Small sampling - Top two from 70 Boss 302's. Bottom twos 69/70 Shelby's

Jeff Speegle

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Offline midlife

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Re: Boss 302 unusual wiring
« Reply #10 on: October 18, 2021, 07:20:48 PM »
Black boot it is.  So...I thought Boss's didn't come with AC, yet you show examples of the AC wiring past the firewall.  I think that answers my basic question:apparently Ford used AC underdash harnesses (at times) for Boss cars, despite not using the integral AC wiring. 

Thanks, all, for an informative discussion.
« Last Edit: October 18, 2021, 07:23:24 PM by midlife »
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