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October 30, 2025 at 10:33 am
#301079
What about using a dual ballast resistor like the Standard Ignition RU-12. I believe one side is approx. 5 ohms and the other side is approx. 1.2 ohms. You could use the 5 ohm side and if needed, add the 1.2 ohm in series. Just a thought. They are not too expensive. In the autos, the ballast resistor was used to cut the voltage to the coil in the run position only. The coil would get 12 volts during cranking for a hotter spark and in the run position, the coil gets the ballast voltage of approx. 9 volts.