It's been my experience, somewhat limited, that an 8v battery was used in a 6v system mainly to cover up trouble that no one wanted to correct properly. Six-volt systems work very well when everything is correct. In fact, 6v batteries usually have better recovery than do 12v batteries. That means they will recover more when discharged than do 12v batteries, because they have more, and thicker plates. All that means is that when you run the battery low in cold weather, it will recover some and let you try a second or third attempt to start the engine. (That used to be the case, anyway- it may not be any more.)
The whole move to 12v systems was mainly because electrical loads were increasing in the mid 1950s, and wire bundles were getting larger, so the solution was a 12v system that required less current for the same work (power), and thus could use smaller wires. The same argument started a few years ago to go to 42-volt systems. That idea fell apart not long ago.
I recommend staying with the 6v system.
Harvester
