6v vs 12v

MSmelcer40

Member
My project 40 ford truck has a 6v system..but I'm missing my generator. The battery is still in and was hooked up....I'm thinking of converting to 12v so I can have a few modern accessories....my resto will be as close to stock as possible....what are the pros and con's to a 12v conversion....thanks and Merry Christmas
 
I guess it comes down to whether you want it judged or not and what accessories you need that only run on 12 volts. If all the wiring is good and the connections are tight 6 volt works fine.
 
Can’t say I ever had any problems specific to 6 volt electrical systems in the two 6 volt vehicles I owned. My understanding is that the switch to 12 volt systems was because electrical power demands increased. Bigger motors with more starter amperage, AC, electric windows, powered convertible tops…. Yes it could have been done with larger 6 volt batteries, heavier gauge wires but that would add weight and more importantly expense. For now I don’t see a jump to a higher voltage system in ICE passenger vehicles as the future will see a conversion to all electric.
 
Overall I had no problems with 6v - starting, running, etc. #0 cables, clean and tight.
Made the change from 6v to 12v on my stock 49. Dim tail lights was the #1 issue. And I tried several ideas to get them brighter, including new wires to the lights, aluminum foil in the housing for added reflection.
If you are missing your generator, there are aftermarket alternators that look like a stock
generator.
If you have questions on the conversion PM me.
 
My fleet is all 12 volts. I have researched the different methods of reducing the voltage to the gauges and tried several methods and products commonly mentioned here, but there always seems to be a problem with some gauge, somewhere. So there is that and I have also heard mentioned the sound and ferocity of the starter engaging the flywheel. Some here have mentioned they miss that nostalgic sound of the six volt cranking and I agree. I have also heard that having the six volt starter changed to 12 volts eliminates these issues. I do love the bright headlights. My wife will often comment when driving home at night in the woodie how much brighter they are than the ones in her subaru! For some strange reason I am currently rehabbing another jailbar tonner. It is slated to receive an H flathead six and I am leaning hard towards the six volt system. And I bet all the gauges will be happy!
 
My truck was fine on 6 volts except for the dim lights. I never tried LED's though. One day an old lady got pissed at me because I couldn't jump start her car in the parking lot and that got me thinking about going 12 volt.

The biggest thing that made me do the switch was installing A/C. I live in AZ. Gotta have it. I did stay with a generator and mechanical regulator as well as points in my distributor.
 
I prefer to keep 6V vehicles 6V. I will admit to converting one car to 12V, but that's only because I couldn't figure out a good way to add air conditioning with 6V and my wife is way more happy to ride in an air conditioned car in Texas.
 
"GB Sisson" mentions problems with voltage drops on the stock gauges. This is the one thing that has stopped me from converting to 12 volts. I am just uncomfortable with the concept, especially with the King-Seeley gauges used by Ford. With the advent of the Optima battery, I have never encountered a problem with a 6 volt system. I think that this may be due in part to the fact that my '51 was an extremely well-maintained 63,000 mile vehicle when I acquired it. The wiring was in excellent shape, and since I have replaced the original starter (that turned out to have a cold solder joint on one of the brushes), it spins over like a new car.

As far as 12 volt accessories are concerned, I made a 6 volt to 12 volt power booster and polarity change device. I now am able to run a backup camera, GPS, CD player, phone charger, and anything else I want. The only thing that won't work is an amp that draws lots of power. It turns out that the polarity change is unnecessary since all of the new stuff comes in plastic cases and needs two wires to function anyway. This, and the fact that the new stuff draws minimal current simplifies the process and allows the use of a cheap voltage booster available almost anywhere.

I am building a flathead powered "T" tub and that car will be 12 volts, as I am using aftermarket 12 volt and mechanical gauges. Because of this, I am comfortable running 12 volts. Then , all of the other justifications kick in.
 
I'm a 12V guy. All my cars have been built either from parts or basket cases or have already been converted to 12V. No judging involved here.
Mart.
 
12 v not judged . I want some no brain needed stuff . Like if I need a jump , or someone else needs a jump , bright lights , easy to purchase , etc
 
If you want box stock truck then I would opt for 6 Volt. Next option would be as mentioned 12 volt look alike generator. Then some of your stock 6 volt accessories may need dropping resistors.
I choose 12 volt when I did the prototyping work to get my 32 back on the road. Its 4:30 Christmas eve, getting dusk, and I can take my truck out with fairly bright headlights. Bright tail lights, and even turn signals. Added safety is a priority for me.

Your truck your choice!

Love those 40 Fords! We need more pictures!
Regards,
Chris
 
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I'm with Mart. In my situation, Same widely-available 24F in everything. Perfect dimensions for a 38 Ford. 64 Xler, 05 Escape & 48 Case. My preferred brand? Walmart Everstart Value of course even though they increased the price to $54. 8^)
 
as already stated 6V works fine its greatest enemy is voltage [bad wires and connections as well as suspect switches if you are willing to deal with this it works fine and now 6v leds are available in saying this 12v is just the same but just more tolerant The only real advantage is its o lot more common so spares [globes /coils etc] are more easily accessible but dont go looking for 6V cd players and such have heard of voltage inverters that change 6V to12V but have had no experience with them so cant comment as to how effective or reliable they are so guess it back to you and where you want to end up
 
Holeshot,
Wow! I didnt know it was that simple. Awesome!
Merry Christmas!
Regards,
Chris


One other important difference between 'Street Rods' & 'Hot Rods'. Street Rods have lawn chairs and Carnauba wax in the trunk.

Hot Rods have spare parts & a tool box in the trunk! DD
.
 
I will never fit in! I have a tool box and no lawn chair!
Hope all is well in Ford land!
Enjoy!
Regards,
Chris
 
I can honestly say that I have never had a problem with the 6v system in my '36 Ford in the 69 years and 94K miles I have owned it. I did find the original reflector headlights to be very limited so I converted to sealed beams. I wired the sealed beam conversion up with a relay, eliminated the original headlight switch on the column in favor of a good dash mounted switch with a foot dimmer on the floor.

My head and tail lights are very bright, especially out on the open road, which I have covered many miles on.
I lived in Eastern Idaho for the first three years that I owned the '36, Idaho winter weather can be very brutal, temps as low as -40 below. The flat head Fords are not the easiest to start in low temps, so I used a 8v battery in the Ford for many years. This was a common practice in Idaho during the good ole days. Any six volt system will handle 8v with no adverse effect to any of the accessories, the only modification required is to turn the voltage up a couple degrees on the regulator.
If a person takes the time to read the directions on the light bulb packing it will be noted that most will say 6/8v.
 
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