Question to the experts.. I've got 2 older Mercs. One is a 9.8 (1968) and a 7.5 (1977). Can either of these be upgraded to a 15HP? I've read on several different forums that this can be done with a carb and exhaust change. In theory, I know that more in and more out = more HP. Is it true? If so, which one can be retrofitted (if either), and what are the #'s of the parts that I need to pull this off. Both outboards run fine but I think it would be cool as a hobby project.
Any and all info is welcome.
Thanks in advance.
Any and all info is welcome.
Thanks in advance.