looking for advise on rebuilding my 454 got the boat as a project and found out one of the cylinders is damaged from not being properly stored so motor needs to be rebored block casting # 3999289 and heads are#353049 . anyways i dont know what this motor has for hp it does say panther marine on the rocker covers id like to do some work to it to bring the hp up as far as i know it has a demon 850 carb and torquer intake manifold i dont want to do much work to the heads but would like to bring the compresion up and change the cam any recomomdation would be much appriceated thanks

starting with the bottom end whats a good comp. ratio  to run on a mildly built engine . and what brand of piston is a common chose for jet boat engines