One of the flyers at our field had the smaller engine, I believe it was a 32 size. It had only slightly more power than the OS 32SX engine, went through amazing amounts of fuel, and was picky to tune. The fuel tank was matched to the size of plane which meant short flight times. After he brought it out about 3 times, he pulled the engine and replaced it with an OS 32SX which was a much better performer all around and only sipped fuel. [8D]