Paul, the group are best situated to give answers to a friends problem.
   He is restoring an old hand pushed sycle  mower powered by a good old
   villiers engine.  The ignition is however cactus and no parts
   available.   Apparently the museum is not as "pure" as others and is
   willing to have an alternative ignition system fitted.  I am assuming
   that there is no spark advance in these engines??  What is a simple
   alternative ignition for an old engine such as this?

   Neil Unger

   I think there are systems on the market that one can program
   spark advance. Maybe MSD.

   Just put "programmable spark advance" in Google.

   Of course the Motec EFI can do that.

   We don't need spark advance for the aircraft rotary as it runs
   over 5000 RPM the vast majority of time so I recommend
   setting  it 22 degrees BTDC and leaving it there.
   A lot of the racers do that as they never get below 8000 RPM.

   Any CD system will work with an old engine with no spark advance or dwell time.
   Ordinary old fashion coils need dwell time which is provided for
   with old points type distributors.

   However the old coils will also work with CD systems.

   Send me some pictures of the front of the engine if you have them.


   Paul Lamar

There are electronic pickups on the market to eliminate  the old points on old briggs engines
They are positioned  on a point to use the magnets  on the flywheel to amplify the signal for switching the coil.
Richie Barrow

Sounds like Hall effect.
Not all engines have rotating magnets.

Paul Lamar

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