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GreatKetch · 12-11-2007, 01:20

This is really basic stuff but it sounds like a remedial lesson is needed...

Your engines are rated for 30 HP AT 6000 RPM. If you have them over-propped and they are only turning 4500 they are NOT putting out 30 HP, in fact not even close to it.

Put the right props on them so they actually put out 30 HP and then come back if performance isn't up to your expectations.

Something to consider, at low speeds wave-making resistence might not be your primary power issue. Skin drag might be the bigger issue, especially if you have a larger than "normal" wetted surface, which I suspect might be the case if you have a tri...

All things said, your performance looks like it is right on the "normal" curve for a boat of that size and weight. You can't fool mother nature.

12-11-2007, 01:20	#9
GreatKetch Registered User Join Date: Jun 2006 Posts: 419	This is really basic stuff but it sounds like a remedial lesson is needed... Your engines are rated for 30 HP AT 6000 RPM. If you have them over-propped and they are only turning 4500 they are NOT putting out 30 HP, in fact not even close to it. Put the right props on them so they actually put out 30 HP and then come back if performance isn't up to your expectations. Something to consider, at low speeds wave-making resistence might not be your primary power issue. Skin drag might be the bigger issue, especially if you have a larger than "normal" wetted surface, which I suspect might be the case if you have a tri... All things said, your performance looks like it is right on the "normal" curve for a boat of that size and weight. You can't fool mother nature.