Spark plugs. Why is it so hard?

RRR,
The BS artist. I make myself relevant to 'every discussion' [your post, #41]. Really? I have very few posts compared to you, do not post if I have nothing to contribute & I am not the one with 75,000 posts.......

And your ignorance about spark plugs continues to grow....not diminish.
Yes, Copper is a good conductor of electricity. But that is NOT why it is used in s/plugs. It is used in spark plugs because of it's great thermal conductivity. If you knew anything about ignition, you would/should know that before the spark current can pass through the copper [ that has a resistance so tiny it could not be measured with an ordinary ohmmeter ] ...it has to first pass through several thousand ohms of coil secondary resistance, the rotor air gap, the resistance in the leads & 3000-6000 ohms of resistor if the plugs are resistor plugs. You think the resistance of the copper is going to make a difference? Dream on...

Copper core.
From the Bosch Automotive Handbook, 3rd edition 852 pages.
Spark plugs, p. 451: " The thermal conduction properties of both the centre & ground electrodes are improved by using a nickel-alloy jacket material & a copper core'.
p.452: ' The use of centre electrode materials with high thermal conductivity [ silver or nickel alloys with copper core makes it possible to lengthen the insulator tip....'
Still on p. 452: 'Electrodes featuring good mixture access to the spark...can be used to ignite even lean mixtures. Larger electrode gaps serve the same objectives [ to extend the misfire limit into the high lambda range.......'
p. 453 : '..the electrode gap should be as wide as possible, so that the spark reaches as large an air-fuel volume as possible & the mixture is rapidly & reliably ignited so that the engine runs smoothly.....It is frequently impossible to achieve smooth idle when the electrode gap is too narrow.'