I just recently finished rebuilding my 1995 150 60 degree intruder. I t runs great. I can run 50 mph on my 19 foot boat. The max rpm is 5000. All six plates in the carbs are open and the prop is only a 17 inch pitch prop. I am also runnning it on a jackplate. Why can't I turn 5800 rpm 's like my other OMC engines.