What pitch prop?

[duckhunter55]

Alright finally got a tiny tac, and found that my 1983 25hp chrysler motor with a 10 3/8x 12.5 prop on my 16ft. mv aluminum jon is only turning, 4300 RPM. The motor says operating range is 4500-5500 RPM. So basically im not even at the lowest RPM range. What prop do you guys suggest, to get my RPMs to the highest i cAN go? My current top speed, by myself is 24 mph and how much more speed should i expect from this change. THanks in advance!

 

[Silvertip]

Re: What pitch prop?

Since you are that far off I would suggest you check the health of your engine. Start with a compression check. For each inch of pitch change (downward) you can expect an increase in engine revs of 150 - 200 RPM. That does not mean speed increases. Less pitch means the engine must run faster to maintain that speed. Since you are so far off the engine may be severely over propped (way too much pitch) so perhaps dropping to a 10 may be all thats needed as the engine can now get over the hump so to speak and make power.