Re: Yamaha f115 versus f150 on 2006 Key West 186 cc
Agree whole heartedly on the test drive, and if you can, schedule it for a day when the water is rough and load up the boat.
We (wife and I) had a 125 Johnson on a 18' Caravelle trihull back in '72. You could load up with the 4 kids and a sunday's worth of goodies and go out for a good time.
The boat was heavy and had a deep v transom area which means it didn't have a lot of "get out of and on top of the water" which translates to a sloppy hole shot (getting up on plane).
We used a 17P SST prop because we wanted to ski and that lower pitch helped us with the hole shot. We didn't have Power Trim and Tilt (PTT) which would have helped also, not a tach so I don't have any idea what Wide Open Throttle (WOT) rpm's were, but they were (had to be) on the high side as she would run 41 max with just me or 39 with the Sunday bunch and purred nicely doing it.
Numerous times we were exposed to rough water and had no problems....but there are ways to handle rough water.
Rough water to me is 4-5 foot waves with a 25 mph wind pushing them. Sometimes capping, sometimes not. Distance between not very much (15-20'). I prefer to get on the water and quarter the waves maintaining a "just on plane speed" rather than staying down in the water (below planing speed) takeing them head on, pound, and eat the spray. I zig zag my way home.
With that said, rough water was no worse for us than normal water. Even if it got rougher, I still would prefer being on top and riding between the wave sort of thing and that significantly reduced the load on the engine as compared to the other style.
So, that translates to not needing more hp for traversing your inlet............butttttt did I want more ponies? You bet. Especially every time a Merc Red band would pull up next to me and flip me the bird,,,,then not-so-politely run off and leave me. :|
It's a tough choice. One thing about more ponies, you don't have to use them if you don't want (but you will....human nature attests to that), and you have to pay for them, and insure them, and feed them, and they weigh more. More butttttts: once the money is spent, it's never coming back and is soon forgotten. But the enjoyment is there for as long as you have the boat.
I guess my advice, after reading the posts and thinking about the old days is that DeeJayCee has the right answer: "Maximum Rated HP is Never Enough".....not suggesting you go overboard, just that you'll use whatever is hanging on the transom and the bigger it is the more fun you will have with it. BTDT.....am there doing that. 8)
HTH,
Mark