speed?

[fairtide]

Here is a possible dock-chat-topic regarding boat speeds. A friend has a Rinker 270 express cruiser with a single gas engine and an outdrive. He is reliable in claims, but I did some on line checking to see what speed that boat is reported to have. Here is the result: so called cruising speed of about 25 miles per hour (statute) and top end between 35 and 40 mph. The engines in reports had varying power outputs, from about 260 to 320 (?). The boat weighs a bit over 7,000 lbs and holds 100 gal. of fuel, At cruising, the mpg (probably statute) is said to be a touch over 2.
I am not trading my 28TE (Yanmar 315) for a Rinker, but maybe someone could explain the vast difference, as I see it, between the speeds of these boats.

[DougSea]

Well...

You weigh 1,500 pounds more than he does, you have a skeg (more stability + more drag), you're propped much differently as a diesel boat.

And once...when the bottom was clean, the prop tuned, and most of my extra stuff left at home, I got Sonny III, with a 1997 Penninsular "Beast" which we all call 300Hp but I believe is actually closer to 290, up to 28knots. That's 32.2 mph.

So, you're much heavier, have more drag, different hull shape, possibly less power, and you're STILL pretty quick!

AND - You can move at cruising speed when the waves slow him down to a crawl!

Edit - And where are the Rinker's numbers coming from? Because EVERYONE markets their boat at it's absolute high end! Flat calm, a midget driving, 2 gallons of fuel...

[jleonard]

the mpg (probably statute) is said to be a touch over 2.

Someone would have to prove that to me. That sounds a little "optimistic" for a boat that is actually cruising.
One thing Doung forgot to mention...YOU will probably still have all your fillings after a 28 knot run...