my best efforts at a rough estimate were something around 3500 kv, and an esc around 150 amp. on 3s 4000 mah lipos.
How about some details about the hull, don't make us guess then give you the wrong recommendations. Brand, pics, etc. would be good. Also, how much
can you spend - how
cheap you want to go is meaningless. Without this info:
The ESC rating is good. Too high a Kv on the motor though. Particularly since you are a beginning boater, you will want a Kv around 2300-2500 for 3S. More may be faster but also more likely to burn up your equipment. You can get plenty of speed out of a 25" boat with the milder motor. High speeds can be fun but on many hulls not designed for them you will spend more time retrieving an upside down boat than running it.
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