I am replacing my Merc 40hp 4 stroke carb outboard , weight 204 lbs, 2.00:1 gear ratio with a 12" pitch prop to a new Merc 60 hp 4 stroke EFI outboard, weight 248 lbs, 1.83:1 gear ratio with a 12" prop.<br />I am concerned about slow trolling speeds .Assuming that the idling rpm's are the same...