6v verses 12v

46fordnut

46fordnut

Senior Member
i am think of change from 6v to 12v...all my electric wire is bare ...pros and cons? stock 1946 ford flat 8 . :confused:
 
I'd fix the wiring first! If you use the original style 6 volt wiring (when you rewire) and want to convert to 12 volts, you'll be fine. Not so if you go the other way... If you do rewire and stay with 6 volts, make sure you have heavy enough battery cables and that all the grounds are good. A 6 volt system in good working order is fine but, if you want to convert to 12 volts to be able to add 12 volt accessories, the 6 volt wiring for the headlights, etc. is fine.
 
Also, make sure the 6V battery is of good quality and the right size. About 20 years ago, the battery in my '51 died, and the only replacement I could find was a Group 1. My car would start fine when cold, but when it was hot (not overheated, but just run a while) I had trouble getting it started. I got in the habit of leaving the hood open when I parked it which helped a lot. I finally replaced it with a 800 CCA Optima which solved all of the hot start problems. (BTW, the Group 1 battery was rated at 425 CCA.)

The last time I was in Fleet Farm, I saw that they had Group 2 batteries that had 725 CCA. I'll try one of those if the Optima ever dies (it's been 12 years now).
 
Hi Tubman - in your 12 years using an Optima 6v battery are there any issues with charging using a regular charge machine - I heard the Optimas have a unique charge process? I never used an Optima but am considering one or a conversion to 12v just yo give peace of mind and quick starting ( and the benefit of 12v bright lights )
 
i'm doing the change for the same reason....plus my wires are shot. to many splices and patches and missing insulation.
 
My 6v wiring is in great shape - though want quick starting and also ease of getting service parts ( 6v not common everywhere. )
A lot of guys say stick with 6 volt - but on a regular driver, 12 v seems the best overall choice . If you go it right , no one will have a clue besides the battery itself.
 
If your headlights (sealed beam) have good wires and grounds, the 6 volts will be just about as bright as the 12 volt. If you are running a 6 or 12 volt generator, your headlights may dim a bit at idle. All of our Flatheads are "drivers", some 6 and some 12 volts. Like I said, if your system (6 or 12 volts) is up to par, you'll have no problems.
 
re wired my 53 f-100 three years ago kept the six volt . good grounds are very important .I run an optima six volt battery also I run six volt halogen head lights,starts right up every time.
 
Mine is 12 V from PO and is neg gnd. Was there a good reason to change from pos gnd?
 
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I have one of each and both can be drivers. As Vic said the headlights are just as bright on both other than at idle. I would definitely go with one of the repro 6 volt harnesses no matter which you choose. You will get a much cleaner looking job that will be easier to work on later. If you stay with 6 you have to deal with converters for accessories and the hassle of trying to jump a 6 if it does die. If you go 12 you have to deal with resistors for the gauges and 6 volt accessories and change all the bulbs. I think there are good reasons for both but have to admit I like the originality of the 6.
 
1963turnerjohn said:
Hi Tubman - in your 12 years using an Optima 6v battery are there any issues with charging using a regular charge machine - I heard the Optimas have a unique charge process? I never used an Optima but am considering one or a conversion to 12v just yo give peace of mind and quick starting ( and the benefit of 12v bright lights )
Click to expand...

No, not really. In my experience, if the Optima has any kind of a charge, a regular charger will work. If it is completely flat, for some reason, you can't charge it with a regular charger. This happened to me one time and I used my variable DC power supply set to about 8 volts to get it going again. I am very happy with this Optima, but several threads on the H.A.M.B. seem to indicate that since the manufacturing of Optima's was moved to Mexico from Colorado, quality has gone to hell. This is why I am looking at a Fleet Farm battery for replacement.
 
I stayed with 6 volts on my 51 mainly because I had a 6v radio, heater and didn't want to mess with the gauges. I did have problems with the overdrive solenoid not always kicking in, but when I changed from a generator to a 6v altenator, it has never failed to work. Plus much better headlights.
 
I have a 55 and a 36 and both have the original 6 volt system and they start and drive with no problems..If engine is good and carb set up properly should not have a problem as they worked when new didn't they..Only once in a parade after the 55 warmed up quite a bit did it get a littlehard to start after sitting for about 5 min..I have learned to shove gas pedal down if hot and not let it up until it starts..DONT pump...Only my few cents worth
 
Ford coupe said:
I have a 55 and a 36 and both have the original 6 volt system and they start and drive with no problems..If engine is good and carb set up properly should not have a problem as they worked when new didn't they..Only once in a parade after the 55 warmed up quite a bit did it get a littlehard to start after sitting for about 5 min..I have learned to shove gas pedal down if hot and not let it up until it starts..DONT pump...Only my few cents worth
Click to expand...

Sounds like a fuel problem and not a battery problem.
 
46 fordnut, I would strongly suggest sticking with 6v wirinng even if you do convert to 12v Tyree Harris is a good person to deal with. I heard a rumor that he even makes some of the harnesses for Carpenter. Like Vic explained in earlier post you can use 6v wiring for 12v. Unfortunately you cannot use 12v wiring on 6v.
this would offer more options in the future should you want originality again. Just my .02
either way I hope you get to enjoy the car!
 
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