I forward an email I received. Gary Gary: The bigger problem is that youve misinterpreted the physics. Once you get to speed, there is a constant force (as well as the transient forces of waves, etc.) of the water resistance trying to slow the boat down. In your lighter boat, this opposing force is lower than it is for the heavier boat. This opposing force not only occurs during the ramp to operating speed, but the entire time the boat is moving. In fact, the resistance (discounting effects of planning) will increase as the speed increases. F = m x a. Force = mass x acceleration. To overcome the greater resistive force, by pushing a greater mass, you have to accelerate more. P = f / t. Power = force divided by the time it is applied. A larger mass x a larger acceleration = a larger force that has to be continuously applied, since youre being continuously decelerated by the resistance of the water. Ergo, you have to apply more power during that period of time. More power = more fuel consumption per unit of time. I couldnt reply to the Power Cat list because I only get the summary Dennis Lee Wimberley, TX