OK Phloop, The spark plug wire is connected to the distributor cap where it gets its charge from the coil. The voltage goes into the capacitor where it builds until it is released to the plug in a single short burst. The reason for the ground wire is because that is how capacitors work. In order to drain them, in this case across the spark plug gap you need a closed circuit thus the ground wire from the negative side of the capacitor.
I am sorry that I was wrong with my last post about not replying to this thread again.
I know how the ignition circuit works. As of yet, I have not seen how these snake oil wires get their charge to begin with.
The coil builds voltage and releases it through the plug wires to the plug's. That is something almost every person knows.
The one thing
I WANT TO KNOW is how the cap's on the wires gain their power to begin with.
Oh and another thing, how do the caps know when to release their energy??
Can some one please dumb this down to where people can understand what these wires do?