Please Help identifying underhood components

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I'm pretty sure "A" is not the VR but rather part of the smog system.

The benefits to headlights relay will unload the light and dimmer switches. The bulkhead connector might not be much of an issue, but might need repair. The big benefit using relays is the wiring "may" be quite small. I don't know if 76 upsized the lighting wiring or not. Also if you put heavier headlamps in, like halogens or etc, the relays are almost a necessity

the 76 does not have "'the usual" bulkhead connector issue because the ammeter is not a "full current" type, but rather external shunt

If you are going to keep the car you really should get you a repop or original shop manual, either paper or "on cd" You cannot download them that late.
 
Well, I will admit that I'm really new to this and now thoroughly confused. I've gone down a big rabbit hole now trying to find articles and discussion on 1976 wiring. From what I can ascertain, and please correct me if I'm wrong, the '76 wiring is actually an upgrade from previous cars? I don't think fusible links are a bad thing to incorporate and the 50 amp stock alternator is good (it seems these big alternators are sought after on the older model cars).

Overall, I will keep trying to learn and do my research.

So will upgrading the headlights with a relay kit on a '76 really help take a load off my electrical system? How beneficial would it be? I did read a discussion about the slight difference in wiring and fusible links incorporated.

Why would Chrysler change out the wiring which worked so long for them on previous cars?
The main battery/alternator circuit which went thru the ammeter was not a good way to do it. That's why most of us with the older cars have bypassed the ammeter by adding a fat wire from the alternator directly to the battery (with an in-line fusible link.) Also, if you are switching to LED headlights, I do not think adding the headlight relay system is going to gain you anything. LEDs draw very little current as compared to the stock bulbs.
 
H'm I see that link to the '76 wiring pdf is now dead. I tried to attach the pdf to this post. Sorry that failed.

Why would Chrysler change out the wiring which worked so long for them on previous cars?
I can only take guesses here. There may be an explanation in the Master Technicians Conference, and if mymopar has fixed their server issues we can look through there.
Gages cost money - even cheap ones. Technology now allowed a fairly cheap remote shunt gage which maybe saved some heavy wiring. The percentage of American drivers who were familiar with and had learned to use gages was less and less. Ammeters can be confusing to those who are not familar with them. There isn't just one correct position for the needle. The driver needs to understand that the normal position depends on the situation.
Another reason may have been that more and more electtrical stuff was being added to both the engine and for the passengers. Electric assisted chokes, warning buzzers, rear window defrost, A/C etc.

I don't think fusible links are a bad thing to incorporate and the 50 amp stock alternator is good (it seems these big alternators are sought after on the older model cars).
If you have a factory 50 amp that is great.
Fusible links are not in themselves a good or bad thing. Mostly they were used to protect the downsteam wires and components from a battery short to ground.
When cars needed hardly any electrical power to run the engine and accessories, having just one link between the battery and everything else made sense.
In this arrangement, the alternator output could flow direct to the main splice without going through the potential source of resistance of a fusible link.
Lets say the car was just started, so the battery needs a recharge and the driver turns on the headlights, wiper, and heater fan.
Since the car was just started, the engine will be spinning around 1700 rpm. At that rpm its probably capable of 40 amps at 14.2 Volts.
Here's my measurements of current flowing to these items on my '85 Grand Wagoneer
upload_2020-9-30_22-49-6-png.png

That's without the brake lights on. So lets add 2.5 amps for brake lights and 10 amps for recharging the battery.
Total alternator output then is 40 amps at 14.3 Volts.

On the standard pre-76 wiring, that 40 amps flows directly to the main splice through either 12 gage or 10 ga wire.
On a diagram current flow would look like this
upload_2021-12-27_11-14-57.png

The major source of resistance to that much flow will be the connectors. Its really pushing the limits of the pushon (Packard 56/58 type) terminals. But imagine if there was also a section of 16 gage wire in that R6 line!
Another moral of the story is let the battery recharge for a minute before turning all the other stuff on.
However the connections could also be addressed as a design weakness. One solution was to use better connections. Another solution is to split the flow path before the connections.
We can see this in at least some 1975 models.
upload_2021-12-27_11-21-18.png



And carried further in 1976.
upload_2021-12-27_11-41-44.png

However be aware that the '76 links are spliced in, so they are harder to replace.
Also, that the currents going to ignition switch and fuse box will be constantly be going through those links. Those links are the smallest wires in the main circuits so we don't want to exceed their capacity. Since youyr not adding anything you should be OK. Still its best to let the battery recharge a bit before turning on heater fan a/c etc. Its also still a good idea to watch the ammeter during recharging if the battery has been really run down. If its pegging (at 40 amps), that's too much current.

So will upgrading the headlights with a relay kit on a '76 really help take a load off my electrical system?
Probably. Its still a long route with many connections from the alternator to the headlights and the '76 diagram still shows only 18 ga wire to the lamps. So connecting directly to the alternator takes some load off the wiring.
 
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Here's a quick graphic of the path for the 9 amps to the headlights.
upload_2021-12-27_11-57-8.png


With relays, that path will see only a fraction of an amp from the headlights being turned on.
Instead the current will flow from the alternator to the headlamps only going through the relay and one breaker or fuse. Being a shorter path, with larger wires and less connections, the lights will also likely be brighter if using a sealed beam or H4 type headlamp. If you are using LED headlamps, then the advantage will likely be much less. That would be somethng to discuss with Stern.
 
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Here's a quick graphic of the path for the 9 amps to the headlights.
View attachment 1715843036

With relays, that path will see only a fraction of an amp from the headlights being turned on.
Instead the current will flow from the alternator to the headlamps only going through the relay and one breaker or fuse. Being a shorter path, with larger wires and less connections, the lights will also likely be brighter if using a sealed beam or H4 type headlamp. If you are using LED headlamps, then the advantage will likely be much less. That would be somethng to discuss with Stern.
Wow just Wow, and folks wonder why this site is by far the most used. The technical knowledge possessed by our members and their absolute willingness to share is unmatched. Well done Mattax.
 
Wow just Wow, and folks wonder why this site is by far the most used. The technical knowledge possessed by our members and their absolute willingness to share is unmatched. Well done Mattax.


Absolutely, I can't say enough good about the amount of knowledge I have gained from this sight and its members that are so willing to reach out and give great, valuable information. It really motivates me to be better and aspire to be that knowledgable one day. It's been a year with my Dart and I've loved every minute of working on it and improving it with the help of these members. I even had RustyRatRod call me by phone and teach me how to set my cars timing. Unbelievable, and am very thankful.

I do have the electrical diagrams for a 1976 Valiant slant six 225 A904, so have been studying those. Thanks Mattax for these diagrams, ill be saving them on my hard drive to reference and studying them.

I will reach out to SlantSixDan (Stern) about my specific situation with a '76 wiring and most likely going to the H4 Nighthawk bulbs, wether the relay kit would be beneficial.

Thanks to all!
 
As far as I know there's no major wiring difference due to engine options.
IF Dan Stern has a source of older halogen sealed beam Nighthawks, that would be decent.
As reported on the Candlepower forum, the more recent Chinese made version lost focus (pun intended).
See here for links and photo comparisons: Crackedback's Harness

When I last looked the lowest price 7" round H4 with a decent pattern and focus was the Hella 'Vision plus' when used with a good bulb. I haven't needed to buy new bulbs in a while so see what Stern (or Virgil on Candlepower forums) has to recommend for current bulbs.
Last year Stern had some Bosch lamp housing for rectangular lamps (and maybe also 7" round) that he had found were comparable to the Cibies he had previously tested.
While these are more expensive than sealed beams (or Hella's Visionplus line) they are still much cheaper than comparible LED headlamps. And some of this comes down to personal preference. That being things like the 'artifacts' as the lighting guys refer to the pattern within the beam. The other being the aesthetics - some kids want the new and cool LED look, and others want something more classic and stylish. ;)
 
Let me try,
A looks like the charging regulator
B looks like a vacuum accumulator/distributor
C looks like the bulkhead wiring connector
D looks like the ignition ballast resistor
E looks like the starter relay
F looks like the electronic ignition module
I think B. Is vacuum amplifier
 
Well, I will admit that I'm really new to this and now thoroughly confused. I've gone down a big rabbit hole now trying to find articles and discussion on 1976 wiring. From what I can ascertain, and please correct me if I'm wrong, the '76 wiring is actually an upgrade from previous cars? I don't think fusible links are a bad thing to incorporate and the 50 amp stock alternator is good (it seems these big alternators are sought after on the older model cars).

Overall, I will keep trying to learn and do my research.

So will upgrading the headlights with a relay kit on a '76 really help take a load off my electrical system? How beneficial would it be? I did read a discussion about the slight difference in wiring and fusible links incorporated.

Why would Chrysler change out the wiring which worked so long for them on previous cars?
Headlight relay kit, see crackedback
 
I'm pretty sure "A" is not the VR but rather part of the smog system.
It does look more like this doesn't it.
upload_2021-12-29_13-6-24.png

Implemented '75 to keep the throttle cracked open on deceleration until the rpms drop below 1500.
Helps preserve the Cat.
https://www.mymopar.com/downloads/mtsc/326.pdf

As far as the vacuum amplifier or transducer, exactly what it is likely shows on the diagram in the engine bay.
upload_2021-12-29_13-15-44.png

Make a photo of that because its specific to your car and options.
 
I always always always recommended bypassing the bulkhead connector for the ammeter wires.

I also recommend running the output stud on the alternator straight to the battery.

I usually catch hell for suggesting either.
Chrysler Corp. already bypassed the ammeter circuit on the 76 model year cars. That is why the ammeter is so "lazy" on all mopars from that date forward. Don't mess with what Ma Mopar already corrected.
 
I'm pretty sure "A" is not the VR but rather part of the smog system.

The benefits to headlights relay will unload the light and dimmer switches. The bulkhead connector might not be much of an issue, but might need repair. The big benefit using relays is the wiring "may" be quite small. I don't know if 76 upsized the lighting wiring or not. Also if you put heavier headlamps in, like halogens or etc, the relays are almost a necessity

the 76 does not have "'the usual" bulkhead connector issue because the ammeter is not a "full current" type, but rather external shunt

If you are going to keep the car you really should get you a repop or original shop manual, either paper or "on cd" You cannot download them that late.
"A" most certainly is the voltage regulater, the blue and green wires go directly to the alternator brushes. And yes, you should carry a spare, along with a spare ballast resister and an ECU.
 
I don't think you can go to NAPA and ask for an extra "D". I think he is looking for the actual components name. I could be wrong.


Oh, and in 3, 2, 1. You are going to be informed to download the free service manual.
Them Ds can be hard to find.
 
Chrysler Corp. already bypassed the ammeter circuit on the 76 model year cars. That is why the ammeter is so "lazy" on all mopars from that date forward. Don't mess with what Ma Mopar already corrected.

They bypassed the ammeter?
 
"A" most certainly is the voltage regulater,
You could be right. I can't see the wire colors or the connector shape in the photo.and I know the location got moved around over the years and options. Should be obvious to the OP, especially the triangular connector.
 
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