Throwing my hands up on this ignition!

Try to run a ECM coil with 22 gauge wire at 9 volts DC and see how bright the spark is.

Same volts but run 14 gauge wires and now see how much brighter the spark is. This is AMPERAGE at work.

The coil it self will draw as many amps the wire will feed to the point of max saturation and nothing more.The coil takes the 9 Volts DC at 15 amps and converts it to 45,000 volts at almost no Amp's.

In a points type Dizzy this AMPERAGE switching is what burns the points out so you must run a condenser to slow down the spikes.

In a MSD system the box takes AMP's and converts it to higher voltage to do the same work.