View Full Version : Fuel efficiency

Kevin Kersten
02-27-2006, 11:27 AM
"! have the chose between a V6 180hp merc. engine on a 27 ft boat or a V8 450hp merc engine on a 25 ft boat

how much would thy use when cursing 20kn? would the V8 use much more, or will it be acceptable?"

04-08-2006, 07:06 PM
"Is the 27' dual drive? That's a lot of boat for a 4.3L. You're going to be pretty far into the throttle on that one for cruising. OTOH, the big block may be overkill on the 25' unless it has a really inefficient hull design."

04-09-2006, 06:57 AM
"Propped correctly, and run at cruise speed, the 454 will get far better gas mileage. Over powered boats always burn less gas (see above conditions) than under powered ones.

For example: Check out the gas mileage of those 'muscle boats' that do 100 mph plus. At cruising speeds some of them make 5 and 6 mpg! I'd murder for gas mileage like that!

On the other side of the coin is my favorite whippng boat--the 32 foot Carver Mariner. These wallowing pigs can barely hold a plane with twin small blocks and can't clear 1 mpg with a tow. Yuck!


05-15-2006, 07:03 PM
Hey Guys. Anyone happen to know what kind of GPH or MPG a 5.7 Vortec might get at cruising speed (i.e. 30-350

05-15-2006, 07:04 PM
Sorry thats 30-35 mph