Bertram33 User Forum

Thanks for the responses. I'm going to try both, adding 1" of pitch and adding a small cup before I launch her this spring. Once I see where that gets me I'll either be happy or have a good idea what else I need to do. I'll post back once I know more.

Thanks for replying. Sorry for the slow response, but didn’t know the answer until I hauled out to clean the bottom. Trans ratio is 2.040:1 (ZF) and current props are 21X20 three blades. Seems like there is plenty of room for more diameter.

I own a 1977 33 FBC with Yanmar 315’s. Specs say it should be propped to reach 3900 rpm at wot, which is 100 over the max 3800 rating. My boat hits 4400 at wot, so it is way under propped. Wondering if anyone with Yanmars knows what diameter/pitch prop is good for this arrangement. Thanks. Btw it lo...