[B_man_Al]

Gasoline ...

Thanks for your kind words !

In your original configuration, .7 ballast, .7 coil, and a wiring resistance of 1.5, the "engine off" current would be 12/(1.5 +.7+.7)=4.1 A.

This would increase by 16% to 4.7A with the engine running due to the ratio of 14v/12V.

The question then becomes is this sufficient current for that particular coil? If it is intended to work with only a .7ohm ballast, the peak current would be 10A with the engine running (14v/(.7+.7) . If this is for a 6V coil and ballast combination it should be fine without the "loom" resistor. If however this is intended for 12V operation, the points will surely burn at 10A pk.

From where you are now, ( 1.4 ohm coil, .7 ballast + 1.5 loom, ) the points should be happy either with or without the .7 ohm ballast. If you go through the same experiment in post 76 you should be able to determine all the voltages and currents involved with your setup.