outboard props.3 blade or 2 ????

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outboard props.3 blade or 2 ????

Postby jus1moore » Sun Mar 14, 2010 9:00 am

Ihave a k&b 7.5 & a 3.5 outboard on tunnel hulls . ive always ran the recomended 2 blade prop on the 7.5 havent ran the 3.5 yet. would the 3 blade give me better proformance on either of these???? the 7.5 flys pretty good now but i like to go a little bit faster ( who dont) no tuned pipes yet. everything is stock. bin thinkin about a hotter carb also on both. any input would be great. thanks
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Postby SteveM » Sun Mar 14, 2010 9:28 am

3-blade props give a bit more rear lift compared to a 2-blade. I've run a X437/3 on the K&B 3.5cc but tended to use the X440/2 or even the X442/2 cut down to the same diameter as the X440. The Prather 215 wasn't too bad as well. The X440/3 was a bit too much blade area for my motors. I was never happy with a 3 blade on my 7.5 outboards.
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Postby HappyOne » Wed May 05, 2010 6:56 pm

Like Steve said, the two blade props seem to work the best. I have used a three blade prop, depending on water conditions, to get the boat up faster coming out of the turns. You should probably have both on hand at the pond.
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