Since the Johnson 90hp and the 115hp are basically the same block and cubic inches, what would have to be changed in order to make a 115hp from a 90hp. I have a 90hp on a 18' Hydra Sport Seahorse Center Console. I have just installed a 13"x15" Michigan Rapture prop and a Hi-Jacker 6" Jack plate trying to improve performance, but the results of installing these items makes me believe that I am probably getting all that I can from my motor as it is. It will run at 38.5 mph @ 5200 rpm w.o.t. with a light load. If any of you have any suggestions I would appreciate it.<br />Thanks<br />Leo
