Recently I bought a used pylon Mustang and two Monza .21 engines. (one for spares)
I tried to find any data on these engines, but so far have not been very successful.

I have run one with a small tuned pipe and 8x6 prop, and it runs very well at about 16,500 rpm.

I would appreciate any information on power/rpm range and propellors to use. Anything, good and bad is welcome. :tired: