Im just curius anyone using a large displacement engine,what size jets do you use?

need more info. too many variables. carb size? head and cam specs? etc.

zz572 crate engine marinized 620 hp
1050 6.5 power valve
731 cam
single plane intake
9.6-1 comp
stock alum heads, 115 chambers

power valves both sides ?, if so, try 85-88 square, but will depent on a lot of things, if no power valve in secondary try about 6 #'s higher there, Rob

You might give Dean Nickerson (Nickerson Performance 215-781-1370) a call and see what he has to say. Don't know how he is about giving out free advice but a phone call doesn't cost much. Maybe get a price from him on tweaking your carb to match your engine and boat specs.

622 N/A 1050 no P/V 96 Squared, hope this helps. Oh ya, I'm at 3600ft.