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Old 01-23-2013, 09:56 AM   #31
knotheadcharters
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City: Jacksonville, FL
Vessel Name: Amar la Vida
Vessel Model: 1989 Carver Californian 48' MY
Join Date: Jan 2011
Posts: 338
Quote:
Originally Posted by Chuck Gould View Post
I've never operated a vessel with mismatched twins, but I'll advance a theory by which that would seem to make sense. Propulsion results from a prop of a given diameter and pitch turning a certain number of RPM. If the gearboxes are the same, and the load is obviously the same on each side, then the engine RPM would need to be the same. Developing that RPM will require X amount of torque and horsepower. The engine rated for slightly higher HP will simply be running at a bit less of its rated capacity in order to turn the prop X times per minute under the same load, but they should be running the same number of RPM.

Or, not. Somebody who has operated a boat with mismatched twins is encouraged to correct my theory if it doesn't apply.
Pretty much what I was saying, there are factors involved, but a little math and some trial and error, a repitch of the props it can be done. Or if you want the ass pain, pull the one or both sell and put in a matched set. Talk to the PO he should be able to give insight.
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