What should coil and ballast resistor voltage be?

1MeanA said
What's the difference between voltage across the coil and voltage from coil + to ground? I get 3V lower across the coil vs coil + to ground. Me and electricity don't see eye to eye :)

The coil negative is switched to ground but it is not AT ground. With breaker points, they have resistance, and duty cycle. With electronic ignition, the negative is likely 1 1/2--2V above ground. This is because of resistance through the switching transistor in the ignition box, which can not be improved