Voltage Upgrade System

If you drive a classic car or truck for any amount of time, you quickly realize that old car headlights are terrible, at least in comparison to what you get with something made in the last 20 years. There are several reasons, but one of the main reasons is that these older cars were wired such that one wire carries ALL the current from the battery to the fuse panel. From the fuse panel, power is routed everywhere and feeds everything.

Wires are like water pipes for electricity. The bigger the pipe, the higher the volume (amperage) you can transport. The more volume you try to transport through any one pipe, the more the pressure (voltage) drops in that pipe. If you have a big wire and only transport a bit of current, you will have a very small voltage drop. If instead you have a small wire and try to transport a lot of current, you will have a large voltage drop. This also shows up in the form of heat transport—too much current through a wire, and it will heat up to the point it melts.

So what does all this have to do with headlights? Well, because there is only one wire feeding the fuse box, that wire has to carry all the current for the ignition, the radio, the heater fan, the windshield wipers, the gauges, and the headlights. To make matters worse, the connectors have corroded over the years, adding resistance, and the headlight on/off switch has plenty of resistance itself. By the time the voltage gets to the headlights, it can be significantly lower than what it is at the battery.