This is the AirPower 38cc gas powered 4 stroke engine. Also know as the A38 OHC engine. Sold at HobbyKing at the time of this video. Its available at some other dealers too. Discussion threads are on both RCG and Flying Giants. This video was made on the first day of engine tuning/running. It is turning a HobbyKing cherry wood 18-8 propeller. These props are as wide as a paint stirrer and often referred to the same. Not the best prop fot fast RPM readings.. The A38 engine is turning the prop at a max 6300 rpm and idles down to a reliable 1650rpm. 1400rpm is possible but not as reliable.