This is like asking who will win the next election. What boat do you have? What prop(s) do you have? What set-up do you have? There is a four part situation to going fast. The driver, the boat, the engine and the prop.
Based on the 1953 APBA rule book here are some facts. 1 mile record 53.321 mph with a Fox (would believe to be homemade as the drivers name is Clay Fox.). 5 mile competition record 46.936 mph, for a hydro again a homemade Jacobsen (Bob). The utility is 49.459 in a mile with a Sid-Craft and 43.859 with a Speedliner in competition. If you get 40 mph going down hill with a good wind behind you, be happy.
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