Originally Posted by JW51
Never considered the 6v ignition being different. Interesting.

Trying to think my way through that….more dwell means more time for the coil to build up voltage and send a stronger spark? Needed more in the 6v setup because you’re beginning point is a lower voltage?

The 66% dwell time gives a stronger magnetic field as the coil builds up to produce a hotter spark when the points break. Using Jon G's improved condenser would probably allow the 12V system to use the longer 6V dwell setting without a danger of point burning and/or metal transfer from one point contact to the other. If the high voltage induced in the primary windings as the points break has not fully dissipated before the points close again, an "arc weld" situation can happen that transfers molten metal from one contact to the other.
Jerry

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