Why not just run a wire from the regulator's grounding point to a known good chassis ground, or even directly to the battery's negative post?

I redid my truck's charging system with all 1AWG welding cable and WOW! It charges like a champ now. I plan to do the same with my girl's Dart at some point. It's okay for now, but eventually it'll get dual batteries wired up with welding cable. A deep cycle to run headlights, stereo and other accessories; and the regular starting battery for running the engine, ignition and starter.

I found that the best way to make your own charging/ground cables is to get heavy duty copper lugs and heavy shrink wrap (I got mine from an Interstate Battery store in Spokane). Strip about a half inch of insulation from the cable Then put the lug in a vice, heat it up with an acetelene (sp?) torch and fill it with lead based solder. While keeping it hot, dip the stripped end of the cable into the molten solder and keep the heat on the lug for a few more seconds so let the cable heat up and absorb the solder. Let it cool and then apply a 1-inch section of the shrink tubing with a heat gun. I was able to get red shrink tubing for my charging cable and black for my ground cables. Charge is solid as a rock now, and my headlights are WAY brighter with the combination of that and the headlight harness I made a couple years back.

This is the method I'll be using for the Dart as well when I get around to it.

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'74 Duster w/ HEI ignition, beat to snot suspension, A904, 8.25" 3.55 SG rear, still being tuned up and gets 17 MPG

Know how they always build a better idiot? That's me

With a decades-old vehicle, there's scarcely any such a thing as a "good chassis ground" through the body sheet metal. Directly to battery negative is a good idea in addition to grounding the regulator base to the alternator housing, not instead of doing so.
...why?

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Great information. I know what I'll be doing on my weekend!

Aah, true point. I hadn't considered the age of the sheet metal. Though why would you only use a wire directly to the battery terminal in addition to the regular ground, and not instead of? Is it because of other electrical stuff being grounded to the body?
Redundancy baby
The use of the deep cycle allows me to use whatever accessories are powered by it without fear of draining the battery if I'm not running the engine. I want the extra reserve of two batteries to power my winch when I install it. The fat cable allows for literally ZERO resistance to the current (I checked it. It's a beautiful thing) and will last a LONG time. Also, if I do something that, for whatever reason, causes the main battery to drain, I can jump it with the deep cycle. The isolator I'm buying is built for just such applications. Hellroaring makes it. I don't know if any of you guys have heard of 'em, but I'm told by many people that they're a great company with outstanding products.

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'74 Duster w/ HEI ignition, beat to snot suspension, A904, 8.25" 3.55 SG rear, still being tuned up and gets 17 MPG

Know how they always build a better idiot? That's me

If you have a continuity checker and your ground checks out you are fine.A ground is a ground.

Actually, that is a very poor way to check a ground. It will tell you if you have a ground, but not if it is a GOOD ground. The best way to check a ground is by the voltage drop, while the circuit is operating.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

That is not correct. A continuity checker is an extremely low-current device, which will show continuity between two points even if they present unacceptable resistance to a load as small as half an amp. Furthermore, even at the same current draw, different kinds of devices have different requirements for quality of ground. Simpler devices are happy with a ground that's good on average. Electronic and computerised devices require a "signal quality" (or "clean") ground. Just ask Sandy in BC or look Here.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

All Sandy said was that he used a larger ground strap.He doesn't mention running it anywhere different.

If electronics require a "signal quality" or "clean ground" why did the egineer's at Chrysler determine that grounding the VR to the firewall was efficient,or all that was necessary?

When the cars were new and everything was fresh and un -rusted/corroded/etc the screws to the firewall worked. Spotwelds between fenders conducted well.

4 decades later spotwelds between fenders don't work so well and corrosion creeps into the wires. Running a ground wire directly to the VR body is just an effective, quick, cheap fix for this.

Also because electronics were not in use in autos in the 1960s, and ground quality for control circuits wasn't as critical. That said, I've cured many cars of "flickering lights and jittering ammeter needle" syndrome with nothing more than a ground wire installed from the (mechanical) regulator's base to the alternator housing. In all cases, a continuity meter showed continuity between the regulator base and the alternator housing without the wire; in all cases that just wasn't good enough.

I'm really not sure what's so hard to understand about this.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Well, I ran a ground wire (14 guage) from the regulator to the alternator housing. However, I couldn't find a place on the alternator to just throw a bolt into, so I used the long bolt that holds the alternator halves together, under the head in the front. I can tell a difference, as now the alternator guage stays steady and shows a slight charge with the lights on, instead of staying in the middle. Hit the brakes, slight discharge and back to charge. Nice. I also moved the ground wire I had on the ECU from the inner fender to the case, under the wire from the regulator to make sure the ground is good. Thanks for the tip Dan and to you other guys for some good discussion.

That's not very accurate. A continuity checker runs a signal of a few milliamps through a connection to test it. A connection that can carry a few milliamps with "as close to zero" resistance as the meter can measure might actually have enough resistance at several amps to provide a very poor ground. And also, there are high frequency components on the line (from the rectified 3-phase output of the alternator, from the ignition, etc.) that sometimes do funny things at marginal connections.

This is also very true on the FEED side of the regulator. On most Chrysler vehicles, a single wire feeds the regulator/alternator field, the ignition, and (on later vehicles) the electric choke heater. The result is that the current flowing through that wire to feed all those loads causes a voltage drop in the wire, so the regulator senses an artificially low voltage. This sometimes results in excessively high voltage out of the alternator, and is a bit rough on batteries and headlamps, and other systems). Its a good idea not only to clean up the GROUND side of things, re-wire things to distribute the ignition load, alternator/regulator load, and electric choke loads a bit better.

In answer to the question "why did Chrysler do it the way they did if its not good enough?" Simple. They really weren't expecting these cars to be driven in the numbers that they are 40 years after they were built. In 1960, there were a LOT fewer 1920 cars on the road (percentage wise and straight numbers wise) than there are 1960 cars on the road today.

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If you have to run a wire to your alt,and it works for you that is great.But you are not getting to what the real problem is in your electrical,bad grounds,connections etc.

My car is a 65,I took the time to go all through it (cleaning grounds,checking wiring etc).I have a electronic VR(hooked up as the factory did,grounded to the firewall)and have no Ammeter jumping problems.

JZ