Spark Plug Question

Shakerhood said:

Either Regular Old Copper Motorcraft or Autolites gapped to Factory Spec of .054

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imp said:

FWIW, do they really use Platinum in these plugs, and in what way? Solid Platinum electrodes would be extremely difficult to fabricate, and cost enormous amounts: the stuff is akin to Gold in value, or more. Why not Gold plugs, then?

They advertise "Platinum" plugs, and "Double Platinum" plugs. What's it mean?

Then, there's Iridium Plugs. (??)

The reality of effects of electrical resistance is that the metal in the plug's electrodes is of no consequence to the resistance present in the circuit. Take plug wires: thousands of ohms in the "Radio Resistance" wire, that in series with the plug gap, millions of ohms there, those two in series with the metal resistance of the plug itself, no ohms to speak of. In the breaker-point era, coils were lucky to develop 15,000 volts. That required small plug gaps, 0.032". Today, 40,000 volts is common, gaps are over 0.050" to give a BIG spark.

IMO, all this hubbub about spark plug materials is, well, just that. imp

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