I was wondering about upgrading the engine on my 2.85m Zodiac solid floor SIB, currently I have a 6hp and the rating plate on the boat states that the maximum engine power allowable is 8hp.
Would it be worthwhile having an extra 2 or 3 hp? I believe it's possible to buy small twin cylinder engines that are smoother also, but would it be worth the effort?
The boat planes easily with the 6hp and will achieve about 14mph with two adults on board.
If it planes easily already, the extra Hp will just mean it will do so with more weight aboard, and / or give you a higher top speed. (Cue prop pitch discussion stage left... )
If it's a new boat, you likley won't have a weight issue on the transom as it will probably have been designed to take the weight of a 4- stroke. The weight issue might be the PITA factor to carry it down the beach!
Thanks for the information.
It seems that to go over 6hp there's a big jump in engine weight, from 25 to 38kg, so probably not worth it for my little SIB.
) 
