I have surfed the need a lot trying to understand this. My 96' GT is in great shape but has over 225k on the clock now. What I want to do since I plan to keep the car is buy a new P.I motor for it and I plan on doing this in the next 2-3 weeks. I have found a 50k mile P.I engine from a 04' Crown Vic. So far I have read that the P.I engines in other Ford cars and trucks are the same right down to the cam grinds and intake. My concern is that the 'Stangs are rated around 260HP and the 04' Vics are rated at 224HP. What gives on the numbers? Some say it's tune, exh, etc, etc but does Ford not rate thier engines at the crank? It would make sense that the cams may be different but the info I have seen is that a P.I motor is a P.I motor so if anyone out there would be kind enough to school me on this I would be greatfull.