I have Hunter 306 and replaced the fixed two blade with a three blade max prop. I installed with the props manufacturer recommendation, 15 X 10. I get 3.5 kts at about 3000 rpm in calm water and was powering into a 20 kt headwind and could only get 1.5 kts, I bit scary. Clearly need to increase the pitch. Has anyone experienced this with a H306 yet and what pitch did you end up with. Pulling the boat out later this week to change the pitch.