merit 25 solo "er"
Join Date: Sep 2013
Location: Columbus, Ga
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Re: ranger 29 sailboat
plus you said max speed so that would mean bigger picth...smaller prop
usually people want more torque for stuff like dropping and anchor and slow speed control so what they do there is go more blades, less pitch(flat blades) on a nice sunflower flat big prop this also ups the rpm range and your cruising rpm goes up quite a bit...good for engine as less wear and tear but you do use more fuel even though the engine is not straining as hard
its a delicate balance honestly...you can have an engine struggling with a bad prop or in happy high rpms...but using a bit more fuel...I prefer the second option...happy rpms less load on the engine
usually when people say they want more speed in fact they want more overall power...overall power can losely be translated to a bigger prop
LOSELY as you can go overboard and strain the engine more than with a small albeit badly pitched prop
if what you want is more ueable power the best thing you can do is get more blades(at the cost of more water resistance when not running i.e drag) and slightly flatten the pitch to get better rpms.
small engines like this as they are less torquey than bigger engines so upping rpm range has the beneifit of keeping momentum up....that does mean however that if you really need to jam the throttle you wont notice such a big difference as with more blades flatter pitch in essence you are losing
hope this didnt confuse us too much
Islander 36 no longer for sale...its MINE!
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Planning maiden cruise for November-December 2015 to Panama Canal! The planning begins!!!