In a boat running light won't net you six mph but just leave your friend on the dock lose some fuel and see where it takes you. Just a good straight line without scrubbing speed could net you a few. But if you do not know what a hook is or dragging tabs that is better left alone for now. Good advice Steve.FYI I wouldn't think he is your friend if you tell him to stay on the dock today I am gonna go faster.Mods may be the better route.

thanks so much for your input

Why not just run the boat with GPS, add 100lbs, easy enough, and run it again before pulling things out of the boat.

My 29' Scarab is very sensitive to weight, the more gas I burn from the tank the faster I go:D(but only a few mph) And yes they do have some major hook, not sure about the 23' bottom though. The hook will prevent the hull from airing out even without the weight.

NO way you will get 6 mph for 500lbs. Maybe 2-3 at most. My 24 outlaw is much more weight sensitve than my 32'.