I have a 17-3 Baystealth tunnel hull with a 2 stroke 90 Yamaha on it. When I first took it out, I was only getting 4300 RPMs and about 31 mph...I then asked Suncoast Propeller over here in the Tampa Bay area, and he said that will lead to over stressing my lower unit because I am supposed to be getting 5600-5800 RPMs out of it. I am wondering what prop I should be running. I currently have a 13x15P and I know that is not the right one.. If anyone has a suggestion on whether I should run a 17P or 19P, feel free to let me know! Thanks guys!