8 volt battery in 6 volt car
 

If using a 8 Volt battery what is the effect on all the 6 volt parts?
Starter motor, all bulbs, coil, generator, horn, 6 volt signal stat, ammeter etc.
Your answers are appreciated.

Re: 8 volt battery in 6 volt car
 

Had a 53 Caddy in high school (1966) 8v marine battery no issues that I recall.

Re: 8 volt battery in 6 volt car
 

Use the "Search" button in the black bar near the top of the page for this subject ("8 volt battery", be sure to use the quote marks). My advice would be to fix what is wrong and not introduce other problems with a patch. Usual problems are dirty grounds and battery cables that are too small (the cables from the local auto parts are probably for 12 volt systems which use smaller cable).

Charlie Stephens

Re: 8 volt battery in 6 volt car
 

Say what??? :eek: :eek:

Take a look at this:

https://youtu.be/LC5SYil9vGw

Re: 8 volt battery in 6 volt car
 

Now that video was worth watching all the way through.I hear lots of people with A's tell me they learned how to do this or that on youtube,Now I see where they get some of these hare brained ideas.I really liked how he changed the timing,and set the carb by turning turning something he had plugging the vacuum port.A's seem to run in spite of people like him.That video dragged on a little at first,but as it went on,it just got fascinating with him thinking he was fixing the car.

Re: 8 volt battery in 6 volt car
 

No kidding. I thought it was priceless.

Re: 8 volt battery in 6 volt car
 

If I changed anything it would be to 12 volts, negative ground.

Charlie Stephens

Re: 8 volt battery in 6 volt car
 

I guess I will have to try again. After the first few minutes I had to stop watching. That guy was making me agitated. :p:p

Re: 8 volt battery in 6 volt car
 

Unrestrained by a battery, a Model A generator will put out up to 32 volts.

Of course many who have issues with the battery connection and find it goes "open circuit" frequently find their headlights and a whole bunch of other bulbs suddenly "burned out." That 32v will do a number.

8V batteries will work just fine if everything else around it is designed for 8 volts. Last I checked, 8 volt light bulbs were pretty much restricted to 9 volt lantern battery spotlights. With the new world of LED headlight bulbs which work fine on 6V or 12V, they'll probably work fine on 8 volts too.

And your starter motor compared to operation on 6V will sound quite "perky" on 8 volts since it is 25 percent higher voltage. If that is your goal, you can use 12V battery with a stock Model A generator and your stock starter will sound REALLY perky at 12v. And you can consider your 12V incandescents bulbs even brighter than 6v 32cp bulbs - which they may be being a modern bulb.

Its all a matter of what you want to do. 8V cell batteries can still be found. NOT like 6V batteries though and you may have to settle for a case size somewhat different than the Model A. 8V Batteries probably more plentiful than 8V bulbs. Might make for a short 6V bulb life unless you have some sort of "dropping resistor" planned.

I myself have stuck pretty much with 6V. Except for that one time I "jumped" the Model A from my regular car - Model A headlights OFF.

Joe K

Re: 8 volt battery in 6 volt car
 

No one has said it, but the cutout would need to be changed. You can buy 8 volt cutouts.

Re: 8 volt battery in 6 volt car
 

Yeah, just wait till you get to the part about setting distributor timing.

Re: 8 volt battery in 6 volt car
 

To answer the original post, Light bulbs are the main thing to consider, Many have said they have converted and are happy with it. The main reason seems to be the brighter lights which will just burn out faster, and a somewhat faster starter. 6-volt starters seem to work very well, and even though they crank slower than converting to 8 or 12 volts, the 6-volt starter in my car does pretty well. I would think that if one is to convert, I would go with 12-volts, negative ground, and an alternator. At least then you would have something more standard. I think going with 8-volts is asking for problems down the road. That's just my opinion.

Re: 8 volt battery in 6 volt car
 

Expect light bulbs to burn out quicker..8 volt not needed A's work good on 6..

Re: 8 volt battery in 6 volt car
 

The guy in the video needs to share all his secrets in a new book. How to repair the model A.

Re: 8 volt battery in 6 volt car
 

I have a bunch of new-old light bulbs for the A.They are Mazda,and the packages are marked 6-8 volt.I don't know if they made 8 volt only bulbs or not,I've never seen any,but that doesn't mean anything.

Re: 8 volt battery in 6 volt car
 

My son runs a 8 volt in his 29 CCPU .The standard generator and cutout charge at 10 amps happily and only slightly warm to the touch after a long run . The coil stays cool and the starter motor seems very happy on 8 volts . The bendix has tight big bolts and good tagged lock washers . It starts easily in cold wet days helped by a hotter spark and more perky starter motor . The spark plugs seem to be unaffected . So far so good the down side is short bulb life if anyone came out with 8 volt bulbs for the A I think there would be a ready market . Just wondering if we could put a suitable resistor in the lighting circuit .The horn seems OK on the extra 2 volts.

John back in cold wet Suffolk County England .

Re: 8 volt battery in 6 volt car
 

The voltage drop of a single resistor would vary with the applied load - more lights, more drop. A better approach may be to use 12V bulbs with 1.5 - 2 times the wattage rating, if you can find them. Approximate wattage of the bulbs - 3/6/10 Cp = 3/6/10 watts; 15 CP = 12W, 21 CP = 18W, 32 CP = 24W, 50 CP = 36W.

Re: 8 volt battery in 6 volt car
 

sofield - Are you just asking for knowledge, or do you have a problem/issue needing to be resolved?

Re: 8 volt battery in 6 volt car
 

Have you watched some of his other videos?

Re: 8 volt battery in 6 volt car
 

No, are there more?

Re: 8 volt battery in 6 volt car
 

Click on his name and it brings up more videos.Not all about Model As but 'interesting'.

Re: 8 volt battery in 6 volt car
 

What an idiot that guy is.

Re: 8 volt battery in 6 volt car
 

I ask the same question awhile back. The replies were a resounding DON’T DO IT!

Re: 8 volt battery in 6 volt car
 

Oh my. Pretty 'interesting', all right. Kind of nutty.

Re: 8 volt battery in 6 volt car
 

I am just looking for a knowledge based cause and effect of this set up has on the various electrical components of a Model A.
Sofield

Re: 8 volt battery in 6 volt car
 

Change this , change that , boost up whatever??? I don't know! , I guess that I have just been darn lucky. Drain the water in the fall, push it in the garage, roll it out in the spring add water ( the WPL) and starts right up … every time for the last 49 years. All stock , like Henry built it. Only one road incident in all that time and 13,000 miles - stopped … bad condenser.

Joe B 31 Coupe

Re: 8 volt battery in 6 volt car
 

Millions of Model A's (and later v-8's) were built and ran very happily on 6 volts. It ain't broke!! It doesn't need to be fixed!! Going to higher voltages masks problems. It doesn't fix them.

Re: 8 volt battery in 6 volt car
 

I would have to say, stick with 6 V, clean all your connections, make sure your battery cables are good, and it’ll crank over like crazy. In my opinion eight volts is just a Band-Aid fix to cover up another problem.
PS. I’m going to install a bolt in my vacuum port to adjust my timing.

Re: 8 volt battery in 6 volt car
 

In my opinion, converting to 8 volts is either a band-aid or it is dinking with something that ain't broke just for the sake of doing it.

Re: 8 volt battery in 6 volt car
 

Now, why didn't Ford think of that?

Re: 8 volt battery in 6 volt car
 

Think of using an 8v battery as the 6V components have to run at voltage and power d1ssapation up to 25 % more than they were rated for. Example - the starter spins faster with more power and the bendix smacks into the flywheel with more force - can it take it? Maybe or maybe not, but they were not designed for the extra force.

Re: 8 volt battery in 6 volt car
 

Were 6 and 8 volt bulbs marketed separately? This has got me to thinking,I have some NOS bulbs,and they are marked 6-8 volt.I have an old Tung-Sol bulb display,that just says 6-8 volt also.While I've never actually looked,I can't recall seeing any 8 volt specific bulbs.I have a big Marquett battery charger,I know it says 6-8 volt on the tag so I gave it another look.there is no switch for the 6 or 8 volt.I drove a 50 Ford pickup for a couple of years that had an 8 volt battery in it.An old mechanic told me that if I took the time to check I would probably find that the battery was being maintained at 6 volts by the stock charging system.He said the 8 volt battery was most likely a feel-good thing by the previous owner.

Re: 8 volt battery in 6 volt car
 

I suspect the 6-8V spec was a feel-good thing pushed by Edison and Westinghouse. They're 6V bulbs. Obviously, running them consistently at 8V will shorten their life.

Re: 8 volt battery in 6 volt car
 

If you want to run an 8 volt battery its simple enough to build a 2 volt voltage reducer with 3 power diodes in series. Check the maximum current draw, then use diodes that are rated for at least double that. Ex: 70 amp diodes are about $5 each on ebay. I don't see any need myself to use anything besides 6V but if its your car, do as you want. Maybe if you have a leaky carb the 8 volt battery will seal it up? :)

Re: 8 volt battery in 6 volt car
 

We buy all these neat old cars and want to experience the unique-ness of having a Model A. Isn't it kind of baffling that one of the first things many of us want to do is mess with some of the basic parts?

Re: 8 volt battery in 6 volt car
 

I have used an 8 volt battery on an old 6 volt tractor, just because it was an easy choice to keep the tractor starting well. But on a Model A, considering, there is a reason 6 volts is not doing the job. I would venture the light bulbs will take the extra voltage but, my choice on my model A would be to figure out why 6 volts was not functioning right. Got a lot investing this ole girl and 6 volts should work.

Re: 8 volt battery in 6 volt car
 

Six volts will work , there really doesn't have to be a problem . There is such a thing as an improvement . My reason for setting up my roadster on twelve volts was that I p[refer a more powerful twelve volt system for the same reasons that most vehicles changed to twelve volts over sixty years ago .

Twelve volt bulbs are readily available . I have NEVER had a problem with the original MODEL A generator or starter when used on twelve volts . I run mine positive ground and no wires will need to be changed or reversed . The biggest thing is installing a twelve volt battery and either using a three OHM coil or installing a resister at the six volt coil . I am now using the Fun Projects twelve volt can style voltage regulator with good results . I have also used the original type cut out on twelve volts . My repro horn blows strong enough on twelve volt to be a good warning device when needed Most six volt accessories will need a voltage resister .

If a person wants to run negative ground It will be necessary toi reverse the wire connections at the ammeter and the coil . Of course the battery will also need to be hooked up negative ground .

Re: 8 volt battery in 6 volt car
 

Re: 8 volt battery in 6 volt car
 

I've got a 40 coupe, still 6 volt, hi-comp heads, dual 97's, headers, electronic ign., a proper grp 2 battery. Spins over just fine ! !
I cleaned ALL the grounds and cables and added another ground strap from the intake to body ground. No problems. FWIW 8V is a bandaid. JMO
Paul in CT