6 Volts

Power is expressed in watts, which equals volts times amps in most circumstances. (Doesn't work exactly that way in motors.) If you double the voltage, you cut the amps in half. A 30 watt lamp would take five amps on six volts, or 2.5 amps on twelve volts. If you cut the amps in half, you can reduce the wire size. It also reduces the effects of any resistances in the line, such as in the wire or at terminals. It reduces the generator current output required to deal with the electrical devices on the car.

Finally, and not trivially at all, it cuts the starting current for the vehicle approximately in half, so instead of a 300-400 amp starting load at worse, you have a 150-200 amp starting load. The cable from the battery to the starter can be smaller, the wires in the starter are smaller, the switch to operate the starter is smaller, and the effects of the resistances is smaller--so they usually start better. While you can expect a well-maintained 6V vehicle will usually start when cold, if you had a few thousand 6V and a few thousand 12V, you'd probably find more of the 12V vehicles starting dependably in cold weather.

Good luck!

For classis vehicle owners that actually drive their vehicles, 12 volt parts and accessories are cheaper and more available.

Since when are we in this to be cheap. My dodge is still 6volts. It starts and runs just fine everytime i want to drive it. Ed

No offense there Ed. I was merely adding why there's a market for the

12V stuff retrofitted to the old 6V. Some of the finest vehicles used 6V with no problems.

Makes it easier to use aftermarket electrical accessories which rely on 12 volts.

I have been thinking about changing to 12 volts on my old 1947 GMC pickup. Here are some reasons not to do it:

The starter must be reconnected for 12 volts or it will die sooner; some of the guages must be adapated to 12 volts; a six-volt radio will need a voltage converter. all of the inside and outside lights have to be changed to 12 volts; a 12 volt battery is needed; a 12 volt generator and regulator or an alternator is neeeded

Some of the problems with six volt systems aren't hard to fix. The main ones involve making really good ground connections, especially between the starter and battery. The headlight ground connections usually need improvements, too. A hot ignition system will help starting in cold weather.

Hi Phil I recall converting my 52 3/4T about 20 or so years ago. Installed a 327 at the time and an alternator. Starter came with the motor, but used a step-down to take care of the gauges. Also changed over the bulbs, but that was the extent of it. The advantages far outweigh the disadvantage when converting over from a Generator. There are whole vehicle wiring kits that can also help you in your conversion and with some minor tweeking, will make the whole process easier.

Mike