How far for prop
 

I build a brushless boat from a cheap plastic boat it did have 2 motors in it and i gutted all that and made my own set up.
question is. How far from back of boat should prop be. I have it sticking out about 3.5in.
But it makes a weird noise. But it does move out in speed and handling.
Any help will be taken.
Thanks guys
Kenny

No one can answer that without knowing the boat type, size, etc. A couple of photos would help us to help you.



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