Well, I for one don't KNOW why resistor plugs would or would not ruin an ignition module, but I can certainly dream up a technical argument for the damaging scenario...

The coil output must drop across the spark plug gap with enough initial voltage to jump the plug gap. A plasma is then created which drops the resistance of the air / fuel vapor to near 0 Ohms, allowing a lower source voltage from the coil to push enough current across the gap to complete the ignition process. If the series resistance of the wired path is too high, the lowered energy flow rate to the gap could be insufficient to sustain the plasma, and the spark will die. For the remainder of the spark cycle, the full output of the coil will then appear across the coil terminals, risking internal breakdown over time. Now I don't know that this would actually occur if resistor plugs are used, but I would like to hear the technical reason refuting this possibility.

Steve

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