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post #12 of Old 10-29-2007
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Originally Posted by GBurton View Post
Is there a recommendation for HP/LBS of boat?
Like most quick rules of thumb this number, pounds per HP needs some common sense to use effectively. The amount of horsepower expressed this way varies quite a bit with length. And surprisingly it decreases as the boat gets larger. The best way to look at it is compare similar boats and in your case compare to other Westsails 32’s.

If you want the base numbers to draw a chart start with,
500 pounds per HP equals a speed length ratio of 1.3
1,000 pounds per HP equals a speed length ratio of 1.05
1,500 pounds per HP equals a speed length ratio of .95
2,000 pounds per HP equals a speed length ratio of .85

If you select 2 HP per 1,000 or 1 HP per 500 pounds you can expect a speed length ration of 1.3 which is high for a Westsail 32 but let’s go with that number and work it out, so with a waterline length of 27.5 feet you can expect a speed of 6.8 knots. This is all based on shaft horsepower not advertised power.
All the best,
Robert Gainer

Study the history of naval architecture and move forward knowing what didnít work before.

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Never design a boat that is weaker then the mast

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