My first boat, 16 Suntracker 18' DLX party barge with Mercury 60 hp. We live in Montana at about 4200' I took it out today for the first time, 4 people, trolling motor and some wind 5-15 mph and at WOT it was only about 4600 rpm, GPS speed 14.6mph, I had about 25 gallons in the 32 gallon tank...