I have a 2005 180fs as well but with a 3.0L Merc. It came with a 14 1/4 x 19 pitch prop. I added the sting ray foil and changed the prop to a 17 inch pitch stainless steel prop to get a better start. I noticed a significant difference. Huge performance gains over the aluminum prop as well becuase of the 3.0L engine, the foil also helped driect the water. After this the boat's run great.