1st Off, I Know This Is Probably Wanna Of The Most Asked Questions On Here... But Anyways.. I Have a 1976 AMF Crestliner Muskie 550 (Trihull) WIth A 70 Horse Johnson WIth A Short Shaft.... I Run 8 Gallons Of Gas.. And 3/4 Adults. As Of Now There Is A 17P Prop On There Now... Plains out Pretty...