Working on bench set up for S1R9A9M9 conversion of 12HP riding mower engine , for running on water vapor pressure and minute amount of hydrogen gas. The original magnetic coil used in 2008 Youtube videos that used 10 amps was reduced to 6 amps as it both forms the field over the ignition wire , as well as firing spark plug. Magnetic field formula is reworked so as same field generated at less amps with increased turns. Protection diodes bank for power supply and battery as series linked 15kv set. 1500v old style Damper diodes are more energy efficient with less waste forward volts and heat, but require less than 15% duty cycle running, which just happens to be this magnet flywheel circuit. High voltage goes through spark plug while amps passes also. The spark timing is ATDC, and only in milliseconds. Inductive ignition is in milliseconds , while CDI is in microseconds. The Briggs on board alternator and diodes are upgraded for more power output, capable of self running system. During the downward travel of piston , the vacuum assists the spark induced expansion of liquid to gaseous state under more pressure. The small current of course generates hydrogen.
The high voltage line requires inductor (that replaces original dual relay coils), of about
4-4.5Millihenries which aids the increase of spark time that's required, as well as the magnetic coil. The 2005-2008 car +18HP Briggs engine successfully used, miniature, original traffic signal relays that had 4 contact gaps contained , with diode, and sealed enclosed in vacuum chamber with outer high dialectric constant black ceramic, for high reliability . These were highly unusual dual coil relays that mechanically switched back and forth if needed, with return springs. Electromechanical relays used to be used in traffic signal power boxes mounted on pole in Georgia. High voltage was applied from car/ lawnmower coil , so as the contacts were actually sparking gaps. Radiant energy may have been evolved that followed conductor to spark plug gap. The magnetic/radiant field was at plug gap until spark plug finished firing. Regular in line coils did not work as well and field dropped too early in timing. (See references to Tesla magnetic spark gap requirements and Website Yahoo groups Waterfuel1978 messages.)
The ignition requires about +12KV DC , (less than +15kv DC protection), which is the hardest section to complete. No protection was used during those S1R9A9M9 2008 videos. Testing now done with hand made intermediate transformer with Briggs/or aftermarket Stens trigger, as preamp volts to regular Briggs Magneto coil, (not SS Magnetron). The much higher volts produced would be put through half wave rectifier as microwave diode. The 30kv pulse AC would reduce down to about the needed +12KVDC. North pole magnet on flywheel provides the free energy, rather than drawing more amps from battery to run a car coil. Initial 19VDC converter and starter starts circuit, then after engine catches, the alternator would run circuit of estimated 18 amps.