So now that I have a 4.5 HP outboard that runs well I would like to
hop it up a little. My last outboard was a 10 HP Merc. I liked the
power. I'm pretty sure the 4.5 HP Johnson will leave me a little
underwhelmed. So I'm thinking about hopping it up a little. If I could
get another 2 HP out of it I would be really happy. So is there
anything fairly simple I can do to up the HP? I don't want spend tons
of time or money but I am willing to do some work this winter. I have
looked on the web but have found precious little about hopping up
outboards except for the really dramatic increases in HP and RPM. I'm
hoping that maybe a larger carb or a different throttle cam or a
thinner head gasket or larger exhaust ports might get me the extra HP
I want. I don't think I have the time to change all the porting. The
exhaust ports are easy to get at but the intake and transfer ports are
not. I'm not looking for much of an increase in RPM, I am instead
looking for an increase in torque so I can use a prop with more pitch.
I have found that a 5 HP motor is fine when it is just me in the boat
but when I have a passenger 10 HP works much better.
Thanks,
Eric