1990 Yami 130 hp on a 1990 Cobia/Robalo SS215 20' with hard top T-top. wot I get 4900 or 5000 rpm. Book says 5500 for this engine. Spare prop(13x17) sold to me with boat. Contacted original owner, said changed prop in 1990, said boat reved to high, put on 13x19. He added hardtop in 1993...