Converting 1988 Merc 20HP to 25HP

[Kwazziee]

My situation is, I have a inflatable rigid bottom inflatable that is rated for 20hp but I use it for fishing so I usually have to pack lots of gear and this adds lots of additional weight. I need a little extra power but minus the extra weights so upgrading to a bigger motor is out of the question.

I did a quick comparison between the 20 and 25 motor using a part catalog and it seems like they are the same motor. The different was the jet itself. There was two jets with the same part number offer for the both so I'm thinking of changing out the jet to make it a 25. Do anyone have experience with this or can lead me in the right direction.

I had an older, late 70"s 18hp Merc that I converted to a 25hp just by changing the carburetor and exhaust.

Any help is greatly appreciated. Thanks.

[Ski]

How about a lower pitch prop

[Kwazziee]

How about a lower pitch prop

I went to a local outboard mechanic and we did some comparison and found it is in fact the same motor. The different was the carburetor and the gasket between the the carburetor and motor has a bigger opening.