If you want the simplest and probably the
most reliable ignition system get a two cycle
two cylinder small outboard ignition system.

Fires the same number of times and 180 degrees
apart just like a 2 rotor.

As close as you will come to a A/C magneto.

http://www.iboats.com/

http://www.iboats.com/Johnson-Stators/dm/view_id.271367

http://www.cdielectronics.com/
Down load the complete catalog.

Some of these stators are as low as $20 used.

The high voltage coils supply 300 volts for a
simple CD system and the other coils supply enough
12 volt current for an EFI system. No belts. If the main
electrical system or alternator fails the engine
still runs.

This stuff is mass produced in the millions and extremely
reliable.

Paul Lamar