Re: 2-stroke vs 4-stroke spark plugs;am I dreaming

[frankr]

That has been around for ages. You hold the pencil in the arc as you hold the wire away from the plug and you can tell whether the spark is of negative or positive polarity by the way the spark "splatters" (my word). Personally, I’m aware of it but have never tried it. As if it really makes any difference anyway. The old V-4 magnetos made two positive and two negative sparks per rev. The cylinders don’t seem to notice.