it’s not a plug gap…
The plug gap is .035
I assure you, Grooveman - the ign system in good condition is perfectly able to jump 1/4". I’ve had it jump a full inch…
The reason for the much lesser plug gap is that the resistance within the cylinder is much higher than in open air. Which should be kept in mind when testing sparking with a plug outside the engine - it should be gapped wider for testing. But also; the plug gap is sort of a minimum to ensure mixture ignition - which may also happen even if the ignition system is less than optimum…
Frank
xj6 85 Sov Europe (UK/NZ)
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