Outrider - it may help some, but a prop and motor can give plenty of short to go damn fast. Crispyspa’s SI3G 1/4 scale SI3 has gone 70mph with just a prop and motor - and this boat is about 25#. The old speed records for those boats using gas engines 30-70cc that topped out at maybe 45mph or so. Build it as light as possible and as aerodynamic as possible.

And it’s a real shock when it blows apart. This crash was his first SI3G. He had two built and went 70mph with the second one.

sorry - I didn’t mean to hijack the thread.