I've put an o-scope voltage probe on the coil - and measured this. This voltage at coil - is going several hundred volts minus relative to ground, so all that is needed for output device protection is a high voltage diode in series with the ECU drive xtr output (not a snubber in shunt/parallel) and it is easy to get a 1000v reverse breakdown diode even 'back in the day' (as I am sure you know). I thought I had some pix of this on the 'scope display, but I only got pix of the details after the arc was fired, when the voltages collapse everwhere. (Once the spark arc is established, it's a short on the system, and the voltages drop like a rock.)
-400 volts x 60 = 24000 volts.... And yes, the 60:1 OR the 46,000 volts may be some nominal value or some special conditions... who knows what the marketing dept did with what numbers LOL.
