ARBoater6789
Recruit
- Joined
- May 30, 2006
- Messages
- 1
Hey long time reader and new forum member here. You guys have unknowingly helped me greatly in the past year and a half as a new boat owner and I need help w/ a prop question.<br /><br />I have a 1983 Imperial I/O runabout with a 120 Mercruiser engine. The prop now is 13 3/4" and 21 pitch. WOT is 4000 rpm and the operating range is 3900-4300. I need a new prop and was wondering if a 14" 19 pitch prop would push my rpm too high (I think that drop in pitch would cause 400 increase in rpm if i'm right?) <br /><br />Thanks in advance!
<br /><br />Your calculations sound correct in theory, but you won't know for sure until you try one. If it pushes it 100 over the limit, don't worry. 500 over and I'd worry!