JSTEW,I had an Allison Foil on my P-Classic and it did help quite a bit. I needed the help with the original 2.5 liter merc but after I switched to the 3.0 liter it didnt need the help and I didnt re-install it. I thought about that for my new one but I just cant get myself to drill holes in the cavitation plate of that $4500 lower unit. Im afraid of any warranty issues with doing that. But, from first hand experience the foils do work well without affecting top end numbers at all. Chris CoupelPaulina, La.Chris CoupelPaulina, La.