8 volt battery in a 6 volt car?

O

old31

Well-known member
Do you see anything wrong with installing a 8 volt battery in a 6 volt car with an alternator.
 
Should work fine with an 8 volt alternator except for the cost, lights burning out quicker and stress on the ignition system. Other than that, go for it. 8^) Jack E/NJ
 
When i got the car they said that the alternator was 8 volt. I have noticed that bulbs have been burning out.

Soooooooo, is there really any advantage to the 8 volt. Maybe more cranking amps?
 
I really don't think that there is an 8 volt battery (golf cart batteries excepted) that has more CCA than a 6 volt Optima. What you really need are good connections, good grounds, and the proper size battery cables.
 
tubman said:
I really don't think that there is an 8 volt battery (golf cart batteries excepted) that has more CCA than a 6 volt Optima. What you really need are good connections, good grounds, and the proper size battery cables.
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100% correct and well stated!
 
8v tractor batteries usually have more CCAs. Jack E/NJ


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The car was built to run with a six volt electrical system. Increasing battery voltage by 33 percent is not a good idea. You can see when bulbs burn out but what about damage to the coil, etc? There is a risk but where’s the gain?

Just put a 6 volt Red Top Optima battery in my 36 Cabriolet and what a difference! Spins over fast and starts instantly. This battery has 800 cold cranking amps which is more than any other battery I could find. The Optima I replaced was in the car for almost 13 years. Good value for $199.99 from Optima with free shipping.
 
Jack E/NJ said:
8v tractor batteries usually have more CCAs. Jack E/NJ


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As we all should know, an Optima is 800 CCA. Generally speaking, you can only get so many watts in a given volume with a lead acid battery. Basic electrical theory tells you you give up car-starting amperage for bulb-destroying voltage. Don't make a lot of sense to me.

Old tractors don't usually have a lot of extras like radios, electrical gauges, heater blower motors, and lights. The lights they do have are usually easily replaced cheap bulbs.
 
Volt-CCA or cold cranking power (watts) delivered to the starter is the main factor. How long that cranking power is able to be delivered determines the size of the battery. Jack E/NJ
 
The wattage is volts x amps. 570 amps at 8v is more than 600 (+) at 6v.
I'm not supporting using an 8v battery, just my opinion that an 8v battery does give more cranking power.

Jack was posting while I was typing
 
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The idea of using a 8v battery has been around forever. To me it seems like a easy "fix" to more problems.
 
an 8 volt battery is a patch for a problem. not only will the bulbs burn out faster, if you want the 8 volt batt to stay properly charged , you will have to adjust the voltage regulator .
 
Lead acid batteries are fine if you like replacing them every few years. Used to buy batteries from a forklift place. Lead acid. Couple years of that and replacement... I bought a optima 6v. Never looked back for 10yrs. Own a couple.
 
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The problem I had with an 8 volt battery was how to charge it when I wasn't driving down the road. So I went back to a 6 volt battery and adjusted the voltage regulator for 7.2 volts and was happy evermore.
 
My '38 Convertible had an 8 volt battery in it when I first got it. A Barn member spotted it right away(I would have probably never noticed) and I switched it back to a 6 volt shortly after. The amp gauge needle had been jumping around like crazy before and settled back to normal after the battery switch. Works fine with the 6 volt battery.
 
Volts and amps are not interchangeable concepts. Electrical theory can get complicated, but think of amps as storage and volts as push. A 6 volt battery can have lots more amps than an 8 volt battery ---- this usually shows itself in the physical size, as bigger size batteries aren't stronger but do last longer. More cranking amps means it will crank for longer (but not any faster) until it dies out.

Back to your question, you can put in an 8 volt battery if you adjust your voltage regulator to properly charge it. Yes, bulbs will be brighter and burn out faster, and your starter may spin quicker, but there is no guarantee that you'll have more cranking amps in storage to crank it for longer.

Personally, I see 8 volt batteries as a band-aid for 6 volt problems. Better to fix the problem than to just cover it up.
 
Better off spending the time and money to make sure your 6V
system is in tip top condition.

If you are intent on changing voltage, convert system to 12V.
 
No, I am not trying to convert or change anything, the 8 volt was in the car when I got it.

I will be taking it out an ordered a 6 v optima. It seems to me I will have less problems, better cranking amps and 15lbs lighter.
 
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