99 Johnson 50hp [upgrade??]

[H20fwler]

I have a 99 50hp Johnson on the back of a 19' boat. It will run the boat at ~ 24mph but it does not have enough power to lift the bow if someone walks up the the front of the boat. the boat is rated for a 150hp but I don't have the cash to remotor right now.

If I remember correctly the 2 cycle 50hp is the same bore/stroke as some bigger motors. Can I bump up the hp by changing carbs?? or is there more involved?

Any thoughts on the good and bad of doing this?

[marshmat]

IIRC, the 1992 to 2004 Johnson 50, 60 and 70 did share some common parts; I don't know for sure if the blocks themselves are identical.
You'd need a good shop manual for that motor to perform any such surgery on it, if it's possible. The carb will probably be the biggest difference but there will likely be a few other things that have to change... all in all, I doubt you'd end up cheaper than just selling this one and buying a used 70 of similar vintage.

[RAWRF]

The 15 hp '99 model Johnson I have as a spare on my Lund has the same block as a 9.9 hp, but the 9.9 has a smaller bore and smaller carb. I assume the same is true of the 50-70 series. You must have a heavy boat, I used to have a 50hp Honda on a 20 foot alum flat bottom with 7 foot beam and it would go over 40mph with a pretty good load. your boat is rated for 150 for a reason, I would start looking on Ebay for something over a hundred HP, boring your engine out wont do that much for your problem.