In 1980 my parents brought me a TF Contender 40 kit (as my first model...), with a Futaba FP-4FN R/C and an HB .40 PDP engine.

Still into the break-in process, the engine threw the TF 10x6 wood prop and jumped to over 20K RPM; apparently, no damage.

A starter cranking attempt, with the engine flooded, resulted in a broken crankshaft and a pretzled con-rod.

I fabricated a crankshaft from steel, straightened the rod and the engine ran, but too little stroke resulted in low compression, so it couldn't idle.
After using an original crank and rod (+ ring, + rear bearing, which shed its retainer; probably because of the thrown prop), the engine ran and it was a real bear. the entire field came over when they heard it run.

The Perry carburettor idle disk made adjusting the idle difficult. The high speed needle couldn't hold its position either and always vibrated open. This resulted in many "dead sticks". So I scavenged a carburettor from an OS FSR engine, filed the spigot to fit into the crankcase and all my problems were solved.

The HB lasted and was installed in an Aviomodelli Tango, until I sold all my R/C stuff and went into 6 years of hibernation...

I am sorry, but I cannot consider the multiple Testors and Cox .049s, as real engines. Besides, they were not R/C, but non-flyable U/C engines.

Sincerely,