8 Volt Battery

[Don St Peter]

I have a restored to original 40 Ply which of course is a 6 Volt system. I'm looking for an 8 Volt battery to install, especially to turn the engine a little faster for starting. I think the existing equipment such as voltage reg, coil, instruments, starter, etc. will be OK for the additional 2 Volts. The farm implement batteries I've seen are to big to fit in the battery compartment under the front seat. Does anyone know a source for such batteries and an opinion of my plan?

Thanks in Advance

Don

[Oldguy48]

I'm sure some others will chime in here with further information, but I'm certain you'll have to adjust the voltage regulator in order to keep the 8 volt battery charged.

[TodFitch]

There have been lots of threads on that topic. So the forum search function is your friend.

My personal opinion is that if the battery cables, starter and engine are in good shape you don't need 8v for better starting.

If you want to change voltage, I can understand why you might want to convert to a 12v negative ground system so you can run modern accessories. But 8v is just a band-aid to cover over problems that ought to just be fixed.

[oldmopar]

Have you checked the usual problems, incorrect battery cable size should be 0 or 1 gauge, are you grounds good and clean

As Tod said a 6 volt system will be enough it is in good condition.

[steveplym]

I put an 8 volt battery in my P-15. I rewired the car, got new cables, etc. and still had problems with a slow crank speed. Now I am very happy with my 8 volt switch. Engine fires right up and lights are bright. I've been running it for about 6 years and haven't blew any bulbs yet. I've got extra headlight bulbs in the trunk if any problems.

I bought mine from a farm implement store. It wasn't that much bigger than the 6 volt battery. What dimensions do you need? I'll measure mine and let you know the brand, etc.

[De Soto Frank]

I would echo Tod's comments.

I've been driving six-volt vehicles for nearly 25 years now, and have not had to use an 8-volt battery or change to 12-volts.

Current antique driver (since 1998) is a tired '41 De Soto; still starts and runs reliably on six-volts. (Car lives outdoors, does not sleep with a "battery-tender" hooked-up to the battery. Usually fires-up within 10 seconds of cranking, even after sitting untouched for a couple of weeks.)

Good luck !

De Soto Frank

[oldmopar]

It also may help if you relocate or add a ground cable on the frame closer to the starter

[Don St Peter]

Thanks for input guys. Steve, I fit your profile, new wiring, right cables, good grounds, etc. My battery box will take a 8" (H) x 7" (L) x8"(W) battery. I would appreciate your measurments and whether you had to tweak your 6 V voltage regulator.

Thanks

Don

[steveplym]

Thanks for input guys. Steve, I fit your profile, new wiring, right cables, good grounds, etc. My battery box will take a 8" (H) x 7" (L) x8"(W) battery. I would appreciate your measurments and whether you had to tweak your 6 V voltage regulator.

Thanks

Don

I measured mine and it is 8 1/2" wide and 6 1/2" across. I didn't measure the height, but I'd say it is about 7" or so. Mine is a Workaholic battery made by Interstate batteries. I bought it at a farm implement store.

I did have to have my voltage regulator tweaked by a mechanic. Then a couple years later I was having problems with the regulator so I ordered one off of ebay that was already set up for the 8 volt battery. It charges great and engine spins right over.

[Norm's Coupe]

I agree with those who said an 8 volt battery isn't needed. If it doesn't start or is hard to start with the 6 volt battery, something else is wrong. I haven't changed any of my wiring, except to add to it for other things. I have 0 gauge battery cables on it. It even started right up before the rebuild. At that time it was only running on 3 1/2 cylinders. Had two broken valve springs, one piece of valve spring stuck in the 3 rd valve spring restricting it and a blown head gasket. Didn't run good at the time, but it always started up ok. I've always run the 6 volt battery in it.

I can let the car sit in the dead of winter when temperatures are around zero for a month or more and she'll start right up. It is kept in the unheated garage, but do not have a battery tender on it, nor do I have to charge it up.