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Old 06-06-2009, 10:24 PM
eggsuckindog eggsuckindog is offline
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Join Date: Mar 2003
Location: Tampa
Posts: 2,354
Default Re: prop time, 18 cc 150 johnson

Quote:
Just got back from the test run with the 15x15 prop. Conditions were a little choppy.

4000 rpm 28.8 mph
5000 rpm 35.7 mph
WOT 5400 rpm 39.5 mph

Egg, thanks for the contact and the 90'/60'info. My 150 is a 90' block.

I think I will use it. Only lost 2.5 mph but the engine will be under less stress with a heavy load. 39.5 or 42 mph is too fast under most conditions in an 18' boat (for an old man).
Makes them much easier to drive at cruise speed in heaveier seas as its not trying fall off plane all the time. Numbers look good
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