merc 15 more power

[nat]

I have a friend who bought a 20 hp suzuki from a dealer he was friends with.His friend told him the only difference between the 20hp and the 25hp was the throttle plate.He ordered the plate for the 25, made the switch and it works great.Is there anything simalar that can be done with my 1990 merc 15? the motor has been stored all these years and is still in new condition.I would like to get a little more out of it without having to trade up.THANKS NAT.

[boats.net]

No sorry I'm not aware of any changes you can make.