IMHO if it is rated for 40 that is what I would go with. I am sure TK or someone with more boat experience will chime in. I have a 14.5 foot Xtreme aluminium boat with a 54 inch bottom.....much lighter boat than you have. It is rated for 40 and it has a 40 four stroke on it. It is a stick steer but I could have gotten it in tiller steer with same motor. If you are going to upgrade might as well do it right.
Regards
|