My boat is a 2000 Alumacraft Tour Pro 175 and has a Johnson 150, currently has a 14 3/4 X 23 aluminum prop, and I can only get 4200 rpms at wot and 45 mph loaded w 4 people. I switch to a 14 3/4 x 21 and I get 4400 rpms and no change in speed with 4 people. Model#J150 PLSIG ser#G04939705. The...
