You need to find out if the 25 is based on a larger block like the present 4 stroke 25.<br /> Based on I think a 36.5 cu.inch 3 cylinder block.<br /> Available as a 25 or 30 I believe the upgrade there would be easy.<br /> Sometimes the best way to more power is to buy a more powerful motor.
Well if 2 stroke outboard is like a motorcycle then you could bore it out and replace the piston, rejet the carb, and replace the reeds, but a new motor might be cheaper.
