I just recently purchased a 87 hydra sport with 87 150 xr2 Black Max. Boat is real sluggish out the whole and will only run 5400 wot. It has a 23p prop. All cylinders have good compression. New stator was put on in March as I was told. Boat only runs 48mph and 5400 rpms. Everything I seen says should at least get 5800-6000 rpms easy.