Thread: prop help?
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Short Wave Sportfishing
 
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On Fri, 10 Sep 2004 03:02:03 GMT, "Tony Thomas"
wrote:

You are exactly right. Dropping to a 21 will increase rpms by about 300 and
drop your speed. You would have to increase rpms by 500 to maintain the
same speed w/ a 2" drop in pitch.

However, something does not add up based on the numbers.
23 x 5400 / 1056 / 1.86 = 63 mph. That means you have a 60% efficiency.
Even if you had a 2:1 gearcase you still have a theoritical speed of 58 mph
which gives a 65% efficiency.


You 'da man!!!!

I never thought of the gear case.

I'll let him know.

Take care.

Tom

"The beatings will stop when morale improves."
E. Teach, 1717