Home › Forum › Ask A Member › 2-stroke vs 4-stroke spark plugs;am I dreaming › Re: 2-stroke vs 4-stroke spark plugs;am I dreaming
An interesting discussion – I’ve never before heard thermionic emission theory applied to the spark plug polarity debate. But it does make sense, if you think about the characteristics of a vacuum diode.
In a vacuum diode, electron current can +only+ flow from the cathode to the plate (anode), else it wouldn’t be a diode. There is also a very small reverse current when the AC switches polarity, but that’s due to a lack of full evacuation of the envelope, which allows the few remaining gas molecules to ionize and conduct a minuscule current from anode to cathode.
If you think about a spark plug in a combustion chamber as an analog of the elements in a vacuum diode – one of which (the center electrode) is much hotter than the other, and so behaves more like the cathode in the vacuum diode, you can conclude that electrons moving from center to outer electrode have greater mobility..
Now that the issue is reasonably well framed, it might be time to test & measure.. who’s up to it? 😉
(Any effect, if real, is measurable.. period.)