Re: what is the right prop?
Before spending money on props: 1) make sure the engine is making full power. A different prop cannot compensate for an engine that is not tuned or simply getting tired. 2) Experiment with setup. Engine height can make a big difference and gain several hundred rpm if it is wrong to start with. The AV plate should be at least even to an inch or two above the keel to begin with. 3) Understand that unless you stay within the same prop manufacturer and prop series, going from a 17P to a 15P may not gain anything or it may gain a bunch. There is more to prop design than simply pitch. Rake, blade shape, cupping, etc are also "design factors". In other words two 15P (or any other pitch) props from two different manufacturers may not, and generally do not, perform the same.
