Okay guys i have a 1996 mercruiser 3.0 lx alpha one. right now it has a 19 pitch (not sure of diameter but i wanna say 14.25") and at WOT im at about 4900-5000 rpms at about 40-44 mph. im obviously overreving. my question is, what pitch should i move to? what diameter? and 3 blade or 4 blade? i...