Hi, just did a new 572 motor on my 26 Scarab
motor sound great but yesterday i tried to give it a bit of throttle but when i accessed the 3000 rpm the motor got over rev and the boat got out of plane .

is it the the propeller to small ?

also i have a holly dominator 1050 and from idling to 2600rpm it has very very rich mixture any help? maybe some one changed jets from stock on can help me out with the jet size?

Bad coupler?

Sometimes you will see a prop hub slip under max conditions,
the merc 540 with headers ran 92 square primary power valve only i believe,. , if the 4500 carb came off a cammy car motor the power valve springs might be a tad on the light side and fattening it up early
and dominators ,also intolerant of exess fuel pressure.