Wrong prop 175 Johnson?

[pbguy420]

I've got a 175 Johnson on my 2100cc that does 44mph Max (gps) with tabs and tilt/trim adjusted perfectly at approx 56-5800rpm...

My buddy with the same exact boat and a 115 merc does 40 mph gps....

Something has to be wrong here? Why am I burning so much more fuel in this much larger engine if I can't go any faster? Do I need to look into props? The guy that owned the boat before me only towed skiers and might have put a prop on it for that purpose....

Anybody with the same engine I have and boat able to run faster???

A guy from my fishing forum thought I should be hitting about 55mph

[freezerfiller]

My 150 only does 41 @5500 so I'd say you're doing about norm for a deep/mod V hull. I'm no expert on perfect setups and the engine is mounted as I bought it, so there might be some secrets there, and I'm willing to learn. Performance is dependent upon loading/gear as well. A full tank of gas is about 500# so I would think I could do a little better on a low tank.

[pbguy420]

I imagine the weight difference of a 115 could help speed a bit but I've always thought 44 seemed sluggish for a 175.... Seems like a waste of hp and fuel. I'll hope for other responses but if it's not a re prop issue then it might be a good idea to see if a shop will trade in for a newer smaller engine...