Hey guys, i have a '75 "california fiberworks" jet boat, basically looks like a spectra mini day cruiser. Almost 23' long, closed bow, no windows, seats 6 comfortably. Never weighed it, but im sure its kinda heavy for its size. Boat has a Hardin marine 460 with a berkely pump spinning a "A" impeller. Engine will spin about 4400-4500rpm WOT, pushing the boat to 48-49 mph on the GPS, with 2 people on board. Does this sound about right for a boat this size with this combo? The 460 has thru transom wet exhaust, only mods are a performer intake and a 750cfm holley vac secondary carb. I would like to get this boat up in the high 50 - low 60mph range, keeping my A impeller. Suggestions? I was also thinking about repowering the boat with a LQ4 or LQ9 6.0 Gen III LSX motor, but with a carb. They make a easy 450 flywheel horsepower by 5000 rpm with a 850 holley, small cam around 210-214 @ .050 and a single plane carb intake....and ive got 7 of them lying around at the moment And it would be stone cold reliable at that HP level, probably better on gas also. I would build the 460.....but i think trying to get anything over 450 horsepower with that motor will require aftermarket heads and some considerable $$$. I could be wrong though, im not a ford guy and it just seems that every post i read from ford forums wind up with HP in the high 300's around 4500rpm, using factory available heads. I dont want to run a solid cam, or even a large cam for that matter, hence my consideration of the LS engine. opinions, Input?