Old school copper tubing wrap and water cooled motor mount..

A 36" boat won't get 40 mph reliably with just 1200 watts, but the 600 motor should be fine (3000+ watts possible). The Kv is on the low side although it isn't much lower than a SV27 or BJ26 motor. Both the hull and the motor can handle an x450 or x452 prop, which should get 40 mph with decent cells. Expect around 100 to 120 amps average as long as the hull runs freely. If you do run 6S then an x445 or x447 will give speeds near 50, but watch for heat. Outrunners like this (again my experience is with Scorpions, not Turnigys) will saturate the windings at not much over 100 amps, turning most of any additional wattage into heat.
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