First of all, thanks for replying to my message. I have a 2006 Advantage 28 sport cat open bow. Love the boat but....496HO is not going to cut it in the near future. Want more just like anyone else and also on a budget, go figure. I am not looking at getting 100 mph but would like to hit the upper 70's low 80's top end and be able to cruise in the 60's without winding the motor up for great lengths. I have a brand new Dart Big M 509 short block with 4340 Eagle/SRP internals Clevite H bearings in my garage. Would you A.) supe up the 496 or B.) complete the engine that i have in the garage? I have a Victor Jr intake and Demon 850 plus a Milodon pan, Hayes flywheel, Summit balancer, Teague crossover with bypass, MSD billet distributor, and some nuts and bolts. Dont have any of the accessories, camshaft, lifters, pushrods, ignition, or pulleys or belts.Would it be it my best interest to consider selling the engine project and getting a supercharger for the 496 or complete the 509 engine project in time? I have a Bravo X outdrive with a Bravo 1 22P prop. What horsepower and torque with pump gas can i achieve this 80+ mph boat ? I am looking for increased mid range punch and overall top performance but my driving habits are mostly cruising with bouts of high end running. My 509 short block is brand new and has the SRP low dome profile pistons #212140 17cc .020 in the hole and i am guessing 9.5 Cr with Childs and Albert Zero Gap Seal rings. If i go the 509 route i would consider using AFR 305 heads with a custom ground camshaft probably from Bob Madera of Marine Kinetics. I I am not in a hurry at all. In fact i thought about getting a labbed 24 prop and seeing how it does with the current set up and maybe some aftermarket Dana Exhaust but i have heard that aftermarket exhaust on a 496 HO with such a big boat doesnt justify the cost. What direction do you think i should take? I want realiablility, and moderate performace. Either way it will be a long term project. thanks for your time, Dave.