Selecting appropriate HP

[Zachdog]

I am considering purchasing a boat with twin engines. I've read articles on the pros and cons of single vs. twin screws. Assuming one were to go with twins, however, what are the main pros/cons of maxing out the HP? For example, on a boat rated for a maximum of 600 HP, standard power is twin 225s; twin 250s are very common, but what about twin 300s? <br /><br />I assume that the most significant factors include price (higher is more expensive); noise (higher is louder) and fuel economy (higher is less fuel efficient). But wouldn't twin 300s running at 4000 rpm be more efficient than twin 225s running at the same rpm? Quieter? <br /><br />Thanks for any advice.

 

[Fouled Plug]

Re: Selecting appropriate HP

I would have to say that running at the same RPM's, the 300's would use more fuel. You may well be going faster with the bigger engines, but more cubes = more fuel to feed them. Now if you wanted to cruise at X knots it might take the 225's spinning at 5000 and the 300's at 4700. But in the end economy might be the same, just a higher potential top speed with the 300's. But I'm willing to bet the sticker shock from the 300 would make a guy choose the 225 or 250.