Re: Is it worth it
I have the exact same boat with a (homemade) floor and casting deck. I have run 1980's-90's Johnson/Evinrudes from 15-30 hp on it. The short version is...25 hp is all you need. Better performance will be had by adjusting trim, prop or engine height.
My experience is that a 15 hp only planes a single +200 lbs man. The 20 hp struggles a bit to put two +200 lbs guys on plane. The 25 hp had a little more hole shot and top speed than the 20 hp, but it also had a higher pitch prop than the 20 hp. The 30 hp I currently run on it using the same cupped prop I purchased for the 20 hp gets two guys on plane quickly and performs great. Add a third guy and performance drops significantly. I also have to change the trim if I carry three.
Also consider that a 30 hp 4 stroke will add a lot more weight and probably eat up any performance advantage. What you can take from my experience with that boat and 2 strokes is that either the 25 or 30 hp are fine. Probably won't see much difference between them. If you want to improve your performance trying trimming your motor differently when you carry three, try a lower pitch prop or even try adjusting the engine height.
I don't know the weight limits off the top of my head, but I think the boat is rated for 800-900 lbs gear + passengers and 400-500 lbs or 3-4 passengers. The weight of the boat alone is around 300 lbs. What max cap is the 400 lbs you noted? Also my capacities are the more stringent Transport Canada numbers not USCG.
