anyone know how many miles I may get a gallon

[ultrasport]

I have a 3.7 4 cyl mercruiser 470 in a 20 foot grady white overnighter cuddy cabin. Was just wondering about how many miles I get to a gallon (maybe 2 to 3?). Boat cruises at 3600 RPMs and goes on average of 25 knots. Thanks.

 

[abj87]

Re: anyone know how many miles I may get a gallon

i get 4 with the same motor so 3-2 sounds right