i have been working on getting this model Best engine running for Tom Madden.
the interesting thing is that they used a 1/4th speed cam gear with 2 exh lobes.
the timing pushrod makes contact on the push and pull of the arm.
the original engine uses a wipe spark igniter, the model was built with a spark plug
i dreamt up the wipe contact timer and had to rework the intake valve plus adjustments
it uses a fly ball governor for hit-n-miss operation.