the6c
New Member
Hi, I'm new to the thread. I have a 21' sea ray walkaround w/cc. It has a 5.0 200 Mercruiser engine. The boat had a 15 1/4 x 15 prop which got between 3800-4000 RPM. I changed to a 14 1/2 19 and am getting 3700 RPM. The boat is supposed to get between 4400-4800. Any recommendations on the correct size?