We need more information to be able to give even SWAG advice:
- what speeds are you looking for?
- what run time are you looking for?
- what voltage are you planning on running?
- exactly what is the jet drive you will be running? (I assume is is a water jet and not an EDF)
- what rpm and wattage does the jet maker recommend?
- where will you be running the boat?
- how have you waterproofed the electrical area?
- how will you recover the model if it stalls in the middle of the pond?
- do you have photos of the model, inside and outside?
Your build is outside the experiences of 99.99% of the members here, but we can at least give you some suggestions once we better understand what you have and what you intend to do.
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