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Having powered the 8000# Cal with a 4Hp outboard during it rescue from the scarp yard i was rather shocked at the amount of stern squat the 4hp was able to produce



Now that its back to normal with a healthy motor and really good propeller



I can put NY NY UNDER WATER at about 6.8 knots :eek:
 

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Discussion Starter · #22 ·
Is there a way to raise the transom mount up a few inches? or will this not be as strong as the original mount?
 

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What speed are you running the motor at?

If you run the motor at full throttle you will not going any faster than half throttle (in light wind conditions), but you will put the motor a lot closer to the water and burn up a lot more fuel.

With a GPS it is easy to figure out what your hull speed is while motoring. Throttle down until you get just below that speed and the boat probably won't squat so much. You'll also get much much better fuel economy (like 2x).

Below hull speed the boat won't squat too much, it'll just go faster. Above hull speed more throttle will just make the boat squat more, but it won't go any faster.

Reserve higher throttle for quick acceleration, deceleration, and pushing with the motor into a high head wind.
 

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Is there a way to raise the transom mount up a few inches? or will this not be as strong as the original mount?
It's certainly possible to raise the threshold of the motor mount, but you probably won't be able to tilt the motor free without enlarging the cutout.. and you'll raise the prop wrt the waterline, reducing performance in any kind of chop.(or need a longer shaft still)

I think you'll find if you back off the throttle you'll be moving fine with less squat and saving on fuel besides....
 

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Discussion Starter · #25 ·
I will give that a try and see what speed im going with less throttle.

thanks everyone. Any other advice please keep posting. Sail net is a great information tool.
 

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that is the "trouble" with displacement hulls.. the faster you go, the more water you displace.
 

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I had a fin on my 16 foot heavy fishing boat. When it was rough, planeing speed was too fast. At about 10 to15 MPH, without the fin the bow would be way up in the air, making it hard to see. The fin solved the problem completely, the bow would stay down at any speed. Not sure how it would work on a displacement hull? One way is to try it, they are not very expensive.

Paul T
 
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