that graph on ebay can not be right, dont believe it. I know my peak hp did not go up with just the pulley swap I know clownhair can shine some more light on the subject. Hes done a lot of experimenting with it. Plain and simple the computer will not let your car boost the hp with just that pulley. Otherwise psifi would not have gone through all that trouble to get the gains that they have made.
Mine --> 2010 Graphite Grey Legacy 2.5GT Limited
Wifes -> 2011 Graphite Grey Legacy 2.5i
"d-pad-4-lifers" member #3