Horsepower Rating

[MathewsMan]

I have a blown 150 on my 20'Center console, deep V boat. Can't remember how much it weighs but with a full 84 gallons of fuel I think its somewhere in the 2500lbs bracket. Less people and gear of course.<br /><br />I thought about replacing the engine rather than rebuild the 150. The 150 2-stroke is in my opinion a little underpowered in my opinion. It does take a while to get on plane even withthe hydofoil I installed. Add a full tank of gas and 4-5 adults with fishing gear and and an ice chest full of beer and ice and you need someone to stand on the bow to get it to plane out.<br /><br />There is a sticker on the transom that says "175hp Max." Is this a rating that they come up with as far as that being the maximum the transom can withstand from a strenth standpoint or is that just what the manufacturer decided would be the max the boat should have in terms of speed???<br /><br />Its a 1995 bayliner Trophy Center COnsole model. <br /><br />I have noticed that in this day and age, just abouot every other boat on the water in the size class my boat is in sports a 200ph minimum and I have even seen 250's on them. So 200's seem to be the norm nawadays for 20'-22' boats.<br /><br />MathewsMan

 

[Laddies]

Re: Horsepower Rating

The HP rating is determined thru rules layed down by the BIA and coast guard

 

[rodbolt]

Re: Horsepower Rating

and no where in the rules can I find any info on structural engineering, just floatation and helmsman ejection specs. speed was not really a part of the equastion, other than the helm had to be able to rotate 180* at top speed without ejecting the helmsman.

 

[MathewsMan]

Re: Horsepower Rating

****Wheels turning****<br /><br />Hummmm??? Somehow I highly doubt I could get through to an actual person at Bayliner...or now that Trophy and bayliner split....an actual person at either one.<br /><br />I guess I can try though.<br /><br />I know they won't recommend it in order to cover thier butts.<br /><br />MM

 

[Booner]

Re: Horsepower Rating

quote by MathewsMan:<br />__________________________________________________<br />It does take a while to get on plane even withthe hydofoil I installed. <br />Hummmm??? Somehow I highly doubt I could get through to an actual person at Bayliner...<br />__________________________________________________<br />Is the outboard at the right height? Just because you have a hydrofoil doesn’t mean that the boat will plain faster. If the outboard is to low it will cause drag. Smart tabs are beater than a hydrofoil. Hit the BIG RED SEARCH BUTTON at the top and do some reading.<br /><br />HUMMMM? Bayliner now that says it all.

 

[steamboatwilly]

Re: Horsepower Rating

I read somewhere that a twenty-foot boat was unlimited h-p by the Coastguard.Maybe anything over twenty-foot was unlimited.

 

[seahorse5]

Re: Horsepower Rating

Here are excerpts from the Federal regulations concerning boat hp ratings:<br /><br />Title 33: Navigation and Navigable Waters<br />PART 183—BOATS AND ASSOCIATED EQUIPMENT <br />Subpart D—Safe Powering <br /><br />§ 183.51 Applicability.<br />This subpart applies to monohull boats less than 20 feet in length, except sailboats, canoes, kayaks, and inflatable boats, that are designed or intended to use one or more outboard motors for propulsion. <br />==========================<br /><br />The maximum horsepower capacity marked on a boat must not exceed the horsepower capacity determined by the computation method discussed in paragraph (a) of this section, or for certain qualifying boats, the performance test method discussed in paragraph (b) of this section.<br /><br />(a) The maximum horsepower capacity must be computed as follows:<br /><br />(1) Compute a factor by multiplying the boat length in feet by the maximum transom width in feet excluding handles and other similar fittings, attachments, and extensions. If the boat does not have a full transom, the transom width is the broadest beam in the aftermost quarter length of the boat.<br /><br />(2) Locate horsepower capacity corresponding to the factor in Table 183.53.<br /><br />(3) For a boat with a factor over 52.5, if the horsepower capacity calculated in Table 183.53 is not an exact multiple of 5, it may be raised to the next exact multiple of 5.<br /><br />(4) For flat bottom hard chine boats with a factor of 52 or less, the horsepower capacity must be reduced by one horsepower capacity increment in Table 183.53.<br /> <br /><br /> Table 183.53_Outboard Boat Horsepower Capacity<br /> [Compute: Factor=Boat LengthxTransom Width]<br /> <br /> <br /> <br />If factor 0-35................................. 36-39 40-42 43-45 46-52<br /> (nearest<br /> integer) is<br />--------------------------------------------------------------------------------------------------------<br />Horsepower 3.................................... 5 7.5 10 15<br /> Capacity is<br />--------------------------------------------------------------------------------------------------------<br /> <br />[Note: For flat bottom hard chine boats, with factor of 52 or less, reduce one capacity limit (e.g. 5 to 3)