When I was a kid we had a family friend who had a Kachina hull (two seater) He first put the boat together with a 427 and topped it off with dual propane carbs. We would get some odd looks when fueling it up. The boat was all motor and tanks. In this configuration the boat ran in the high 80's. A few seasons later he went to Twin Holley's and a blower. he also did the lower end but I have no idea what he bored it to, and he would never tell. Running on av-gas he was topped out at 102 MPH. We confirmed the speed using radar. The boat had some work done on the jet but nothing too radical. I know y'all will think I'm full of shit, but I was skiing behind it at the time. The things we do at 18.