actually a 12v battery should/can only produce 12v ... the alternator produces 14v [or so] to keep the battery charged while running the components, and if the system is #1, the headlights should be getting as much power as they were designed for, and producing the full candlepower rated for stated longevity
my comment above relates to the fact that some here have said using an 8v battery on a 6v system resulted in shortened bulb life ... seems it might be the same with 14v on a 12v system, would be curious to hear if that's the case
I've been driving old trucks as designed for decades, and never had a lite switch fry, and if I had it happen repeatedly, I'd sure wanna find out why!
Bill
