I am curious about putting a torque shift prop on my older boat, I wonder if the difference would be worth the money. I have an 86 with a Merc 170. It seems like from what I have read that this is an application where it would make a huge difference. Of course at what point do you decide to stop putting money into a $3500 boat? I would like to see skiiers get up a little faster and it seems like this would do it. Any help for a newbie?