Hi, I've got a 660mm speed boat single hull with a few mods, its was all fine until I put a faster motor on, now I'm getting nose dives and what I think is cavitating. I have moved everything back as far as it can all go, now this boat came with a 3s but now I have 2x 2s lipos and a 90a esc, so as you can imagine its tight in there :/ with all the wiring and the cooling etc. But it still nose dives, I've checked the angle of the prop to the hull and all is good (it may ne possible its ventilation) the issue I have is the nose diving!!!! With all the weight at less than 30% of the rear end of the boat (using scales) how do i both prevent nose diving but also stop ventilation? To me it seems very odd and very frustrating. I've done all sorts to try and fix it but it seems that steady throttle and slow speed is ok, if i wanted that i wouldn't have upgraded a speed boat
please, any idea and any tips or even criticism is certainly welcome.
thanks
George
(Also I used trim tabs but removed them as the issue is too low nose, i removed them to make sure it wasnt them causing ventilation)
P.s. I'm not aloud to post photos until I have been a member for longer, sorry about that

Without knowing the boat, it is hard to say, so guesswork appears. It might be that you have found the limit of what that hull design can do. There comes a point where just applying more power doesn't make the boat go any faster, it just misbehaves.

Typical hit-and-run thread. The OP hasn’t been back to the forum since he posted ten days ago, guess he either solved his problem or it isn’t that important to him.