49 Merc Flathead V8 original 6 volt generator: What should my regulator charge the battery at? I ponied up for a #4 6 Volt Battery, It's big and carries lots of reserve capacity. The specific gravity of it new was 1225 in all cells. The battery voltage reads as 6.46 volts with no load and engine off. What should I set the charging rate at when setting up the regulator? At $130 bucks, I don't want to over charge this battery .