1 wire verse stock multi wire alternator clarification

[culp71]

ok so I need some engine bay wiring help...
the American auto wire kit 510289 specifies that it only supports use of higher current self exciting 1 wire alternators...
expressing its concern that stock alternator cant handle the high current draw for electric fan, aftermarket stereo system, ac system, air ride, fuel injection, etc.
since I have none of this, cant I use a stock wired style alternator?
if not, do they sell a stock a looking 1 wire alternator for a 71 cuda that only generates 25-60 amps not the 100 or higher like most 1 wire alternators?

further reading informs me that it will not support use of the stock ammeter either.
again due to the higher 100 amp alternator output...if I am able to find a lower amp alternator can I wire it parallel with charge system to the stock ammeter?

[Cuda Cody]

That's over my level of wiring knowledge.   

I just use stock wiring so my simple mind can grasp it.   

[culp71]

I apologize for all the weird electrical questions but only ever have restored 40's and 50's vehicles which have a completely different charging system.

[cuda hunter]

So, I just got my 67 barracuda back.  It had a wrong alternator on it.

I needed a two pulley which it had.  But the mechanic had wired the choke into one of the field wires. The green one.
I removed the choke from that system. 
There was a second field wire that was just hanging out inside of the tape.  Was not hooked up. 
The altenator that was on the engine was a 69 amp single field connection. 
I went through hell to find what I wanted through the local parts stores.
The only one I'm looking for is a 65 amp, double pulley, with two field spade connectors.
finally after two altenator's that were supposed to be right I found the correct altenator.
Specifically a 65 amp.  A little higher than the standard 55-60 amp single field connector.  The only 55-60 ampers that I found only had one field wire connection.

So, when you go to the parts store you should only be able to find an altenator up to 60 amps with one field wire.  Just have to make sure you don't need the double pulley.  Everything you can get is what should work for you in that lower amperage.

Did that help or explain anything?

[ratroaster]

Read here at the link below. This is a good explanation.... I bought a rebuilt older design single wire unit for the stock apearance and converted it to the newer 2 wire design for the newer regulator designed for electronic ignition. You can get a new brush kit for a few bucks from Rockauto.  Basically you are replacing the brush that was grounded to the case with one that is Isolated.  http://www.imperialclub.com/Repair/Electrical/charging.htm

[1 Wild R/T]

A little clarification... What American Auto Wire id calling a one wire alternator isn't the same as most folks call a Mopar one wire alternator...

It truly only has one wire, the big battery wire... They are based on a GM alternator core & rather then applying power or ground to excite the field (well actually they still do, but with a twist) these alternators have an RPM switch, they won't charge till the rotors spins fast enough to close the switch & if the rpm's drop to low it will shut off....

69 & earlier Mopar's had an alternator with one side of the fields grounded & the voltage regulator apply 12v to the other side of the field which excites the windings causing the system to charge.... This design voltage regulator originally used points & coils to control the alternator...  Many refer to these as "one wire" or "single field" alternators

70 & later Mopar's had an alternator with both sides of the alternator field isolated & when ever the ignition is on 12v is applied to one side of the field... The second connection to the field is from the green wire on the voltage regulator  which applies ground to excite the field...  These were the first electronic voltage regulators... Many refer to these as "two wire" or dual field" alternators....  In fact bothe designs are single field alternators...

Something that confuses the issue is all the 69 & earlier alternators were whats called "round back" design....  And 70-71 alternators which have the fully isolated field designed to work with the electronic voltage regulator were also of the "round back" design....

Starting in 72 the alternator design was changed to what's call the "square back" design.... 

Many  electrical rebuilders aren't aware of the 70-71 oddball alternators & yet those are the ones many E body owners want....

[ratroaster]

I gotcha Wild R/T.... I totally misunderstood what he was after.  Good explanation!

[Chryco Psycho]

So the first question is this , how much amp output do you need , if you are running a lot of extras the 60 amp alt may not keep up .
Any Charge wire you run in parallel to the main charge wire going through the ammeter will reduce the load going through the ammeter , this is a good idea & the ammeter may still deflect a little to show charge

[culp71]

okay so what are my options then?

at this point I don't care if the ammeter gauge is connected or functions.
I simply want to make it work , look stock and be safe.
so I can run the engine for the first time and get, carb, cam, timing etc. all break-in and set.
I want it to be safe, with no fire risk regarding the charge system.

I do want it to look stock. but since the AAW system doesn't support this, what are my options?
stock electronic ignition with no high draw electronics or systems.
I would like to stay with a lower amp alternator.

so:

1.elimnatie ammeter, put in a ugly gm style 1 wire alternator and wire?

2.leave original style alternator and wire how? eliminate ammeter?


anyone running a AAW set up in a 70-74 non modified e body setup?

[1 Wild R/T]

For the stock system to work you need the alternator, the regulator & a single switched 12v wire, this will the the wire shown as existing ignition on 12v.....

Use the AAW alternator to battery wire as the one shown as Batt existing.... 

This should explain it... If not LMK..

[culp71]

that seems very simple...thank you

so with that setup can the org ammeter gauge be wired in?

[1 Wild R/T]

AAW doesn't route the load or the charge all through a single wire so making the ammeter work would be a PITA.... And it truly is a bad choice.... Convert to a voltmeter...  Ammeters were ok back when these cars were built but even then a voltmeter was a better option but as the years go by the resistance in the circuit creates to many problems, why build those problems back into your new wiring

[culp71]

good point, so for now I'll wire system as shown in the picture, and not connect ammeter but rather rework the stock face into a volt meter. ill try this wiring method tonight see if I have any other issues wiring it this way starting with a AAW system.

[culp71]

a response from AAW specifies a one wire must be used and ammeter must be replaced w voltage.
my concern is that ugly god-y looking chrome alternator... as now I have a stock replacement installed and it looks right. I hate the look of the chrome aftermarket ones. especially when so much care was taking else where to  keep the original look...so since I can only find a "square back style" chromed 1 wire alternator...

I will be doing what 1 WILD R/T said to do, ill leave the stock style alternator, eliminate the ammeter gauge and route like this.
I'm sure AAW is only going to say to do it their way as a company policy. I trust this ebody community as they have never steered me wrong..

what gauge wire should I use for this alteration?

[1 Wild R/T]

The wire AAW provides is the charge wire, theirs should be more than enough.... The field wires are low amperage control wiring 18 gauge is fine....

AAW builds Chevies, knows Chevies & doesn't want to have to think of anything other than Chevies.... In spite of that they make decent wiring....