Mopar performance alternator 1or 2 wire???

[MerlinsMopar]

Mancini has this alternator which states that it is 1 wire compatible but I have a later 2 wire external voltage regulator. The pic shows another terminal with a wire from inside it hooked up. IE a ground, I guess. Can I disconnect that wire and hook up the other wire?
They are having a sale till the 14th and I wanna get it but this got me stumped on weather it would work.
Thx for the input. I'm sure someone will know!

 

[Johnny Dart]

Not sure if this is what you are doing, but generally if you are switching from a 1 wire (single field) round alternaror to a 2 wire (2 field) square back alternator, the second field wire jumps to ground on the alternator. Do a Google search on the subject to be sure.

PS: Now that I look at your picture, it looks as though they already grounded the second field wire for you. Bolt in on and go !

 

[wish4hemi]

It is a one-wire and I would recommend leaving it that way. You can see the exact same alternator (different finish) installed here:

Gallery: Vying For Voltage With A Mopar 110-Amp One-Wire Alternator - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech

 

[67Dart273]

Mancini has this alternator which states that it is 1 wire compatible but I have a later 2 wire external voltage regulator. The pic shows another terminal with a wire from inside it hooked up. IE a ground, I guess. Can I disconnect that wire and hook up the other wire?
They are having a sale till the 14th and I wanna get it but this got me stumped on weather it would work.
Thx for the input. I'm sure someone will know!

View attachment 1715688749

View attachment 1715688750

Judging from the photo they have added a "non standard' "internal" regulator (the green wire) and grounded the remaining field terminal by removing the insulating hardware

Is your regulator, the one you are considering using, is it 69/ earlier, or 70 later?

If it's 69 earlier you should be able to remove the green/ internal regulator and just hook it up

HOWEVER IF you have done nothing to solve the "typical" old mopar bulkhead connector issues AND the voltalge drop issues from the battery--the path through the ignition switch--and to the factory regulator IT WILL overcharge.

Also a "one wire" needs to have a MUCH larger charge wire than 3 wire systems, because the sensing is on the charge wire.

 

[Mattax]

I wanna get it but this got me stumped on weather it would work.

If you want to get this because it claims to have a 110 amp rating and that sounds good, unfortunately its a gimmick. Unless your car is routinely drawing 50 or 60 amps and it has been rewired to handle those loads that alt is just trouble waiting to happen (see post 4 for why).

 

[Dana67Dart]

Mancini has this alternator which states that it is 1 wire compatible but I have a later 2 wire external voltage regulator

I would say that with your later model VR with 2 field wires you are taking a chance that the wire connected to the field connector is a ground. I would be more on the "just pull off the ground wire group" if the wire was terminated to the outside of the case.

It is logical to assume that the wire is a ground BUT... You won't know till you get it. Do some ohm tests before you hook it up.

 

[chinze57]

Judging from the photo they have added a "non standard' "internal" regulator (the green wire) and grounded the remaining field terminal by removing the insulating hardware

Is your regulator, the one you are considering using, is it 69/ earlier, or 70 later?

If it's 69 earlier you should be able to remove the green/ internal regulator and just hook it up

HOWEVER IF you have done nothing to solve the "typical" old mopar bulkhead connector issues AND the voltalge drop issues from the battery--the path through the ignition switch--and to the factory regulator IT WILL overcharge.

Also a "one wire" needs to have a MUCH larger charge wire than 3 wire systems, because the sensing is on the charge wire.

Out of curiosity, what’s the typical issue with the bulkhead connectors? Just rewired the car with a ron Francis kit but kept the bulkhead connector. Took it apart and installed new terminals in it but kept the bulkhead connector to maintain separate wire harnesses between dash and engine.

Will that solve the problem? Plan on putting a more powerful alternator on later to power electric fans and such

 

[Mattax]

Out of curiosity, what’s the typical issue with the bulkhead connectors? Just rewired the car with a ron Francis kit but kept the bulkhead connector. Took it apart and installed new terminals in it but kept the bulkhead connector to maintain separate wire harnesses between dash and engine.

Will that solve the problem? Plan on putting a more powerful alternator on later to power electric fans and such

What year car?
And how was it optioned, electrically?
Yes it makes a difference

 

[chinze57]

What year car?
And how was it optioned, electrically?
Yes it makes a difference

1964 dart. All new wires, all new fuse box, connectors, etc.

Originally it had a radio from the factory but that was it for options. The bulkhead was actually disassembled and the connectors inside of it were replaced with new ones to be sure no 60 year old parts were being used electrically.

 

[Mattax]

1964 dart. All new wires, all new fuse box, connectors, etc.

Originally it had a radio from the factory but that was it for options. The bulkhead was actually disassembled and the connectors inside of it were replaced with new ones to be sure no 60 year old parts were being used electrically.

If I recall (correct me if I'm wrong for '64) all of the wires connect at the bulkhead using a Packard 58 or Packard 56 type terminal.
One of the issues with these is the somewhat limited contact surfaces, and the other is like any terminal, the wire to terminal crimps.
The highest current flow is going to be in the alternator output wire.
The next highest flow can be through the battery charging wire. If the battery has been severely discharged, or repeatedly discharged (for example by running electric fans) then this circuit gets used a lot and more severely.

IIRC only 1963 and 1965 have ring terminal type connection through the firewall for these two circuits. Better clamping, more contact surface area, and more exposure to air for cooling.

 

[Mattax]

If you're going to add electric fans then think about how you are going to run them.

If you are going to run the fans after the engine is shut off, then its best to have some sort of rewiring. A different wiring strategy is needed.

If they are only going to run when the engine is running, you can get away with a circuit on relays. Do it just like a headlight relay circuit.
The way to 'get away' with this will be by making sure the alternator chosen has the ability to produce enough power to run the fans, plus the engine's ignition, brake lights, and anything else electric needed at slow idle speed. The key will be ability to produce power at slow idle speed.

Alternator 'ratings' are always at some rpm well above idle. On top of that there's other games manufacturers use to pump up the numbers. What you will need to know is power (watts) or amps at 14 Volts at idle rpm. Why 14 V? Because the battery is at 12.5 Volts (give or take). So if the alternator can't make the power at a Voltage above that, then battery is going to become the power source.

Here's an example of current flow.

In this example above the alternator needs to produce 31 amps.
By adding a second power distribution point to an auxillery relay/fuse box in the engine bay 20 amps have been diverted from having to go through the firewall.

 

[MerlinsMopar]

I have the later 71+ regulator. I dont need 110 amp either. The car has a green and blue field wire along with the main battery wire. I wanted this alternator because it was black but they only have the black 1 with 1 field wire. Just confused on why they show 2 field wires on it but only made to use on a 1 wire car.

 

[chinze57]

If you're going to add electric fans then think about how you are going to run them.

If you are going to run the fans after the engine is shut off, then its best to have some sort of rewiring. A different wiring strategy is needed.

If they are only going to run when the engine is running, you can get away with a circuit on relays. Do it just like a headlight relay circuit.
The way to 'get away' with this will be by making sure the alternator chosen has the ability to produce enough power to run the fans, plus the engine's ignition, brake lights, and anything else electric needed at slow idle speed. The key will be ability to produce power at slow idle speed.

Alternator 'ratings' are always at some rpm well above idle. On top of that there's other games manufacturers use to pump up the numbers. What you will need to know is power (watts) or amps at 14 Volts at idle rpm. Why 14 V? Because the battery is at 12.5 Volts (give or take). So if the alternator can't make the power at a Voltage above that, then battery is going to become the power source.

Here's an example of current flow.
View attachment 1715688895
In this example above the alternator needs to produce 31 amps.
By adding a second power distribution point to an auxillery relay/fuse box in the engine bay 20 amps have been diverted from having to go through the firewall.

Excellent information thank you. The Ron Francis fuse box has a circuit for the fan and controller wiring, but Instead of running those connections through the bulkhead connector I could run them through a grommet in the firewall to power them.

I’ll need to find a powerful enough alternator, which seems to be the issue. Currently have LED’s everywhere except for headlights, and no real aftermarket accessories, but the fans im looking at use 40w.

 

[Mattax]

I have the later 71+ regulator. I dont need 110 amp either. The car has a green and blue field wire along with the main battery wire. I wanted this alternator because it was black but they only have the black 1 with 1 field wire. Just confused on why they show 2 field wires on it but only made to use on a 1 wire car.

Thanks. That clarifies it.
Tuff-stuff sells (or used to sell) a black finished revised squareback.
I have one. I was not impressed.
It's my opinion that it draws more field current than some of the regulators can handle.
I suspect this is typical of revised squarebacks but may be amplified by the rotor windings used to create higher output alternators.

If you really want a black finish you can use a regular squareback and strip it down for painting with minimal masking. Be sure that where the bolts and spacers go remain or get sanded to bare metal. While the input current gets its ground connection through the voltage regulator, the ouput current is grounded through the casting.

Take a look at the sticky posts on how to identify Chrysler alternators. That may clarify the two terminals versus one, and from that how a 'one wire' internally regulated alternator was made.

 

[MerlinsMopar]

Thanks. That clarifies it.
Tuff-stuff sells (or used to sell) a black finished revised squareback.
I have one. I was not impressed.
It's my opinion that it draws more field current than some of the regulators can handle.
I suspect this is typical of revised squarebacks but may be amplified by the rotor windings used to create higher output alternators.

If you really want a black finish you can use a regular squareback and strip it down for painting with minimal masking. Be sure that where the bolts and spacers go remain or get sanded to bare metal. While the input current gets its ground connection through the voltage regulator, the ouput current is grounded through the casting.

Take a look at the sticky posts on how to identify Chrysler alternators. That may clarify the two terminals versus one, and from that how a 'one wire' internally regulated alternator was made.

I called mancini and apparently this alternater has a built in vr so you just bypass the external one. That sounds easy enough but I am gonna have to look at some ele diagrams to be sure it is wired right.

 

[Mattax]

Excellent information thank you. The Ron Francis fuse box has a circuit for the fan and controller wiring, but Instead of running those connections through the bulkhead connector I could run them through a grommet in the firewall to power them.

I’ll need to find a powerful enough alternator, which seems to be the issue. Currently have LED’s everywhere except for headlights, and no real aftermarket accessories, but the fans im looking at use 40w.

40 W at 12 Volts would be roughly 3.5 amps. If running two then 7 amps.
Keep in mind most equipment draws more power when given at a higher voltage. So to be safe figure 8 to 9 amps.

Circuits off the fuse box would probably be OK. Even 10 feet of 14 ga wire isn't going to cause much resistance to 9 amps. The resistance will be in the alternator output wire, especially the connector, when that 9 amps is added in.

The daytime running power normally needed is around 4 amps.
Now with fans on that becomes 13 amps.
With all lights on (no relay) add around 12 more amps (depends on how many lights and which bulbs)
At a stop light, add brake lights. Yours may be less with the LED but its something.
Add heater, and wipers.
That total will give a pretty good idea of the load while driving in the worst situation.

Off the top of my head in a stock '64 it probably was around 25 to 30 amps.

The big variable is the state of the battery. If the battery is low, it will want to draw current for recharging. So immediately after starting there will be a short period of time when another 5, 10, 15 or more amps will be flowing through the alternator output wire. The factory alternators help limit battery recharge from becoming excessive because they're maximum output at slow idle is somewhat limited. (They're no guarentee. At fast idle they can produce plenty of power - we see examples more than we'ld like of pegged ammeters getting ignored. The meters show 40 amps in each direction -anything close to 40 to or from the battery is getting excessive. )

With cooling fans, unlike all of the rest of the equipment, when the car is stopped is when the they are needed most. This is unfortunately when the alternator is running the slowest. IF the battery is continually discharged under such conditions, then it will want more and more recharge current when alternator speed picks up during off-idle.

 

[Mattax]

I called mancini and apparently this alternater has a built in vr so you just bypass the external one. That sounds easy enough but I am gonna have to look at some ele diagrams to be sure it is wired right.

As @67Dart273 mentioned above, you can do that, but its not a good idea.
If your car is a '69, you also need to be cognizant that this will disable the feed to the distributor.

 

[MerlinsMopar]

As @67Dart273 mentioned above, you can do that, but its not a good idea.
If your car is a '69, you also need to be cognizant that this will disable the feed to the distributor.

Its a 71' also I am using msd. I actually converted my 68 cuda to a 2 wire circuit. The other wire just looped back into the other circuit.

 

[Mattax]

You guys may find these interesting and useful.
Measured current draw of typical equipment

Illustration of small resistance causing increasing problems with higher current.
Keep in mind that when voltage drops, that means power was used.
When it drops due to resistance, the energy is being used to create heat!

Charging Battery with Alternator - Warning
Skim through this - especially the sequence where I recharge a low battery.

 

[MerlinsMopar]

Judging from the photo they have added a "non standard' "internal" regulator (the green wire) and grounded the remaining field terminal by removing the insulating hardware

Is your regulator, the one you are considering using, is it 69/ earlier, or 70 later?

If it's 69 earlier you should be able to remove the green/ internal regulator and just hook it up

HOWEVER IF you have done nothing to solve the "typical" old mopar bulkhead connector issues AND the voltalge drop issues from the battery--the path through the ignition switch--and to the factory regulator IT WILL overcharge.

Also a "one wire" needs to have a MUCH larger charge wire than 3 wire systems, because the sensing is on the charge wire.

The car has the later style VR with a green and blue wire. Mancini stated to just bypass the VR and it will work since it has an internal regulator. Do you think that would cause any issues? I am not running any ele fans/ pump etc. Maybe an amplifier for a stereo but thats about it other than standard lights etc. I will be using msd.
Thx

 

[Mattax]

Its a 71' also I am using msd. I actually converted my 68 cuda to a 2 wire circuit. The other wire just looped back into the other circuit.

It will still face the issue of voltage drops and with that the flip situation as to when running the external regulator. Increasing current through resistance in the output circuit will result in lower system voltage. This means everything runs worse and the battery may be undercharged. When it does charge it may then charge at excessive rates.

Also keep in mind if you need to replace it its not a stock item. That's something important to me but may not be a factor for you.

 

[67Dart273]

Out of curiosity, what’s the typical issue with the bulkhead connectors? Just rewired the car with a ron Francis kit but kept the bulkhead connector. Took it apart and installed new terminals in it but kept the bulkhead connector to maintain separate wire harnesses between dash and engine.

Will that solve the problem? Plan on putting a more powerful alternator on later to power electric fans and such

I don't recall (without looking it up) does your car have the BIG feed through terminals for the ammeter? I think these are screw terminals. Mopar did this one or two, then skipped a year. If you have the regular size bulkhead terminals for the ammeter, this is part of the problem. If you have the very large feed through that is normally NOT a problem. Other areas of voltage drop are simply "follow the path to the VR from the battery. So main problems are ammeter circuit through the bulkhead, ignition switch and connector, bulkhead terminal for the ignition "run" feed.

One way "around" is to electrically cut the ignition "run" feed coming into the engine bay. Us the key switch end to trigger a relay, feed the relay from the starter relay, and hook the switched contact to the engine bay end of the cut wire.

Other concerns is making sure the firewall/ block/ battery all see a good ground/ common, and that the VR is grounded to that