Quote Originally Posted by phillnjack View Post
too me I would say your running too low, not too high. the prop dont fit the gearcase and is getting way too much exhaust flow over the blades for a start.. this will cause a load of performance on that type of prop in your situation.. but the 1 inch up in every foot is a crazy thing as it would mean a 6 inch jack plate you only go up 1/2 inch ? and a 12 inch jack plate you only go up 1 inch ? seriously, who the hell came up with that daft formula. most people buy a 6 inch jack plate and go up 4 inch straight away. to be back that far on the gill bracket I would be going up higher..... look at the way the bracket bottom is and compare that to your ventilation plate because thats where the water is coming from.. get rid of the gap between prop and hub will get rid of a lot of your cavitation.. just my thoughts on what I see.
I'm doing a 24 Superboat like that now i/o boat got a 30 inch bracket and 250 mer c 25 inch mid trying to figure how high to go out bracket