I have a Narwhal IB 2.80m with inflatable keel & floor. I currently have 4hp (2 stroke) mariner but am considering getting a bigger engine so that I can have a bit more fun! The boat is officially rated upto to 8hp but could I go to 9.8hp & will I see a big difference versus my 4hp? Thanks
A 2.8m with a 9.8 2-stroke (you thinking Tohatsu?) will be very lively one or two up... completely different to a 4hp.
There have been several threads here on going above the makers hp spec and every opinion has merit but having experienced transom problems even with the correct hp I'd stick to the makers advice.
Before my upgrade to an 18hp Tohatsu from Yamaha 8hp 2stroke my 3.5ae Honwave (quite heavy) would go great with myself and my 7 year old son (i am 15stone he is about 3.5stone).
I was amazed how well the sib went with just me in the boat with the little 8hp so i would think a 2.8 sib would go really well with the stated 8hp.
I only upgraded cause the Mrs started to come out with us and that slowed us down quite a bit (only 10 stone!) but thats enough of a difference in weight to really slow it down.Would still plane easily but conditions had to be good.
