I have a 07 Tahoe q6 sport 21ft open bow with 5.0mpi currently running a 14.25x19 ss prop I noticed last few times out with 3 adults and 2 kids weighing 110ibs max together and 3/4 tank of fuel that it just boggy coming out of the hole and it wasn't like this before that I can recall.. It runs smooth no misses or anything like that.. I don't have any books for the boat my question is do the 5.0 not like low grade fuel? 87-89 octane or is there other things to look into? Noticed today semi calm water wot trimmed out it would only run 45 @4,000 rpm before I could turn 4500 rpm easy .. Thanks y'all
