How many harnesses are there

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Holy Roller

Holy Roller

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In the engine bay on a 68 barracuda, is there supposed to be 2 wiring harnesses or just 1? Does one harness connect to the firewall, go to the engine and connect to a second harness that finishes the engine/electrical boxes and also goes to the headlights and marker lights. Or is there just one combination harness? Thank you
 
So this is like a trick question,
As was answered in your other thread, the bulkhead connectors in a '68 Barracuda are somewhat organized with:
Main power and run circuits in the middle, along with engine sensors.
Wiper motor (but not washer) and backup lights along with A/C.
Lighting, plus power to close starter relay, plus brake failure switch.

Now how are the wires bundled for routing? - that's a different question. On '67, wires for the wiper are bundled seperate. '68 is prob the same but someone else will know for sure.
 
I don't know about 68 but my 67 Barracuda it is all one, both the engine harness and forward lamp harness are assembled as one. I think if you pop a few terminals from the bulkhead connector you can split them. I know there were some changes in 68, the horn relay was relocated for one.


Alan
 
Battery charge/feed wire was moved from bulkhead position Z to J in '68.
 
Cuda Al said:
I don't know about 68 but my 67 Barracuda it is all one, both the engine harness and forward lamp harness are assembled as one. I think if you pop a few terminals from the bulkhead connector you can split them. I know there were some changes in 68, the horn relay was relocated for one.


Alan
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That's what I'm trying to figure out..if the engine/ forward light harness is the only one I need. Or is there another harness that works with the engine/ forward light harness. When I bought my car, all the wiring was messed up and cut. I don't want to buy a harness I don't need. If that makes any sense.
 
The wires from the bulkhead connectors go directly to their final destinations.
Many of the wires from the from middle and inner connectors are bundled together with a non-stick electrical tape for routing.

A big question is why did the previous owner modify?
> Was it just field repairs because something was failing or was something altered?
> Altered could be a home made 'improvement' (maybe it was, but never know)
> It could have been additional equipment; stereo with amp, electric fans, electronic ignition...etc.
 
Mattax said:
The wires from the bulkhead connectors go directly to their final destinations.
Many of the wires from the from middle and inner connectors are bundled together with a non-stick electrical tape for routing.

A big question is why did the previous owner modify?
> Was it just field repairs because something was failing or was something altered?
> Altered could be a home made 'improvement' (maybe it was, but never know)
> It could have been additional equipment; stereo with amp, electric fans, electronic ignition...etc.
Click to expand...
Not sure, but it was all cut up and cracked and not usable.
 
If you have a new Engine/Forward Lamp harness that is all you need.

Alan
 
Holy Roller said:
Thank you Alan, I didn't want have to pay 130.00 for a harness I don't need. Some places don't do returns on electrical things.
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It's hard for me to make heads or tails of Classics' harnesses. Some look to be generic.
Which one are you looking at? $130 is pretty cheap. The one Year One lists is basically correct, and judging from the one I bought 25 years ago (which may have been different supplier than now) the quality was OK.

Holy Roller said:
Not sure, but it was all cut up and cracked and not usable.
Click to expand...
So car itself is all original? no additions or mods? If so, yes like Alan said a repop which has both connectors should be fine.
 
Mattax said:
It's hard for me to make heads or tails of Classics' harnesses. Which one are you looking at? $130 is pretty cheap. The one Year One lists is basically correct, and judging from the one I bought 25 years ago (which may have been different supplier than now) the quality was OK.


So car itself is all original? no additions or mods? If so, yes like Alan said a repop which has both connectors should be fine.
Click to expand...
I'm using MSD pro billet distributor with the 6AL box and tach controller also.
 
Ok. With the MSD 6A you should be able to use the stock harness without having to cut into anything.
 
Basic 6 series is wired as shown here.
Heavy Red with ring terminal can be attached as close to a source of power. Either battery at solenoid as in the instructions, or alternator's "Bat" stud. There's pros and cons to each. Alternator is my preference but battery is Ok too. At most it will draw 3 amps or so highway (3000 rpm), and 6 amps at 6000 rpm (dragstrip).

Heavy Black - Engine.

On-Off. Join this to the factory coil power wire. (Blue. Ignition 1 in the service manual diagram). Mount it on an insulating board using a bolt and spade connection. These used to come with MSD box and maybe still do. See picture. Leave the ballast resistor and connections. This way the on/off wire will get power whenever the ignition switch is in either run (blue wire to ballast to blue wire) or start (brown wire connected to blue wire at ballast). This draws very little power - just enough to turn on an internalswitch in the MSD.

Autotronics1498p4.JPG


IMG_7951.JPG
 
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The advantage to taking power at the alternator is its higher voltage, and it ammeter will always read correctly. It's also protected from a battery short - although I think that's a minor concern with this particular device. The disadvantages are distance if the box is mounted on the driver side, and may not be as 'clean' as power closer to the battery.

It's hard to know now, so many years later, why MSD suggested battery source rather than alternator. But when charging circuits are equiped with an ammeter, its better not to add equipment to the battery side. Again, loads here are not high, so don't sweat it. It just means the ammeter may show slight charging when in fact its just power going to the MSD box.
Understanding Charging Systems with Ammeter
 
Looking at the year one harness. Does this plug in or have wires spliced
 
Mattax said:
The advantage to taking power at the alternator is its higher voltage, and it ammeter will always read correctly. It's also protected from a battery short - although I think that's a minor concern with this particular device. The disadvantages are distance if the box is mounted on the driver side, and may not be as 'clean' as power closer to the battery.

It's hard to know now, so many years later, why MSD suggested battery source rather than alternator. But when charging circuits are equiped with an ammeter, its better not to add equipment to the battery side. Again, loads here are not high, so don't sweat it. It just means the ammeter may show slight charging when in fact its just power going to the MSD box.
Understanding Charging Systems with Ammeter
Click to expand...
Thank you Mattax, how do you like those MSD plug wires?
 
Tadams said:
Looking at the year one harness. Does this plug in or have wires spliced
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Not sure Tadams, I bought my wires from classic industries and they are like factory harnesses . Right now, until midnight tonight...they have FREE GROUND SHIPPING and UP TO 20%OFF IF YOU SPEND 149.00 OR MORE. If your buying wiring harnesses, 149.00 is not hard to spend. You can get more that one and get a percentage off and get it shipped FREE.
 
Holy Roller said:
Thank you Mattax, how do you like those MSD plug wires?
Click to expand...
They've held up well. The insulation is too fat for stock wire holders, but for non-stock its fine. When I decided to try the e-core type coil with the standard cap, that requires making up a custom wire. Oddly they don't have a coil wire for Chrysler going straight up and then to a sparkplug type connection at the coil. So I bought the H1 Jaw for my wire crimper, a spare coil wire and parts to make my own.
 
I'll be honest guys, if you drive at night a fair amount and don't need 100% stock look, consider a headlight relay like Rob (crackedback) makes. In my experience its the one circuit that's really weak, a lot of connections and the small wires. His harness is plug in and IMO better than increasing the wire sizes on the original headlight circuit (again unless looking original is important).

On any reproduction harness, there are no splices for the end user to make. The costs are in the labor, parts, and details. If you look at the original posted in the other thread you'll see it even retains the factory part number (white label). Pretty cool.

One more suggestion. Save your old harness. You or someone else may be looking for parts off of it, or reference it for any number of things. I'm so glad I saved mine. Some sections of wire will be trashed, but a lot won't be, and the connectors generally are not either.
 
Mattax said:
They've held up well. The insulation is too fat for stock wire holders, but for non-stock its fine. When I decided to try the e-core type coil with the standard cap, that requires making up a custom wire. Oddly they don't have a coil wire for Chrysler going straight up and then to a sparkplug type connection at the coil. So I bought the H1 Jaw for my wire crimper, a spare coil wire and parts to make my own.
Click to expand...
I think I might go with the MSD wires myself, Taylor has some good ones too.
 
Mattax said:
I'll be honest guys, if you drive at night a fair amount and don't need 100% stock look, consider a headlight relay like Rob (crackedback) makes. In my experience its the one circuit that's really weak, a lot of connections and the small wires. His harness is plug in and IMO better than increasing the wire sizes on the original headlight circuit (again unless looking original is important).

On any reproduction harness, there are no splices for the end user to make. The costs are in the labor, parts, and details. If you look at the original posted in the other thread you'll see it even retains the factory part number (white label). Pretty cool.

One more suggestion. Save your old harness. You or someone else may be looking for parts off of it, or reference it for any number of things. I'm so glad I saved mine. Some sections of wire will be trashed, but a lot won't be, and the connectors generally are not either.
Click to expand...
Good advice
 
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