M

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M

J

I hope this helps lol

M

lmao, true, but i dont need a 16 foot monster, looking bout a 10-12 foot johnboat.

B

Now ya want to know how I found it, I typed, "what formula should i use to determine weight capacity of my boat" into Google.

J

Now ya want to know how I found it, I typed, "what formula should i use to determine weight capacity of my boat" into Google.

What is "Google"? I've never heard of this before.....

G

Now ya want to know how I found it, I typed, "what formula should i use to determine weight capacity of my boat" into Google.

You've always got an answer, I like that.

B

What can I say I gotta lot of spare time. LOL

M

we talking bout the same thing? last time i was googleing i forgot to lock the door...

B

Lol

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max hp is 2X( hull length in feet X beam in feet) -90 so to get 25 hp rating in 12 ft of boat one would need a 5 ft beam

so for example... 12 ft boat 5 ft wide... =60X2 =120 -90 equals30 hp.....maximum rated.... most mfg drop this number around 10 percent for overloading and safety and cheeper liability insurance..... my little go fast was rated at 175 hp..... its 7.5' wide and 17.5 ft long....

so 17.5X7.5 X2 =262.5 - 90 is 172.5 so heres where things get tricky.... numbers are rounded to the nearest higher 5 hp.... thus the 175 rating..... but the USCG is more concerned with weight than actual hp so thus the reason i can run a 245 or 260 or 280 or even a 2.5L 300 hp motor on it because those engines are all the same weight as a production 175 and so thus they still meet the level floatation requirements set by the USCG and as such are not over powered according to the posted capacites plate....

my alumaweld is actually derated based on that formula..

20X8X2 is 320-90 is 230..... it was derated to 145 prop/200 jet.... because alumaweld didn't want the liability payment full rating would cause... which is a waste being the boat isn't even goverened by that standard..

so for example... 12 ft boat 5 ft wide... =60X2 =120 -90 equals30 hp.....maximum rated.... most mfg drop this number around 10 percent for overloading and safety and cheeper liability insurance..... my little go fast was rated at 175 hp..... its 7.5' wide and 17.5 ft long....

so 17.5X7.5 X2 =262.5 - 90 is 172.5 so heres where things get tricky.... numbers are rounded to the nearest higher 5 hp.... thus the 175 rating..... but the USCG is more concerned with weight than actual hp so thus the reason i can run a 245 or 260 or 280 or even a 2.5L 300 hp motor on it because those engines are all the same weight as a production 175 and so thus they still meet the level floatation requirements set by the USCG and as such are not over powered according to the posted capacites plate....

my alumaweld is actually derated based on that formula..

20X8X2 is 320-90 is 230..... it was derated to 145 prop/200 jet.... because alumaweld didn't want the liability payment full rating would cause... which is a waste being the boat isn't even goverened by that standard..

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J

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