I have a 1972 Conyplex contest 33. I am planning on running 48 volts 200 amps max for one minute which should get me close to 14 horse power . Horses don't matter Torgue and RPM's is what I worry about.
Every thing I saw while looking at electric mentioned the same thing. You don't need as much horse power to run a boat on electric because you lose horse power through the engine/Trans to the prop. Electric is more responsive, cleaner, and more efficient. You will have to change out your prop to a 3 blade prop though which means more drag. The other side of that coin is the when the electric motor turns you actually produce power.
I bought my kit from Cloud electric. It is their electric motor kit and paid a more then reasonable price for it.
I had been researching this subject for a while and just decided to take the plunge. I am not looking to motor sail so I will be using it to get in and out of the marina I'm in. I went to the controller website last night and saw that there is a wiring kit for my particular controller for 19 dollars so I will be buying that as well instead of wiring it up myself. The only thing I want and need to find out about the electric motor when installed is just how good is how it performs going through a channel against a tide that moves quickly. I am pretty sure it will handle it but I will find that out first when I install it.
Here is a good video to watch. It is a Catamaran though so he has 2 electric drives and says he only needs half of what he has. Watch all of them because it is interesting what he says about the electric drives producing power while sailing. It makes me think I will add a resistor to my system just to dump any excess power.