not to be redundant but i posted in my last post that these are "fat wallet upgrades." if the guy wants to try them i dont see a problem, im just trying to help him understand that heads and a cam are not enuff to make huge amounts of power, it has to be used in conjunction of the other mods done to the rest of the system in order for it to make a difference. sludge is right it is easier/cheaper to throw on a turbo or super and make more power for your money, but ultimately if your looking for huge numbers the heads and the rest w/ the turbo super will make an added increase cuz your letting the engine breathe and can take extra boost. only one problem, the factory hypereutectic pistons and cast rods cant take that much boost. if your going to do all of the above and make huge amounts of hp your goin to need a forged bottom end, and the only one readily available (w/o custom ordering from manufacturers) is the 3.3 kit. since my motors toast im doing all of the above and am hoping to make 300 hp, but this is strictly to keep mustangs in check and a timeslip, not practical for daily usage. (i may decide to use it daily but for the most part shell drink a lot of gas...) its your motor and your money you decide on what you want from it, but as far as just slapping heads and a cam on it and calling it good dont waste the money. for the power dif go w/ a light forced induction setup or do little things like regearing underdriving headers and a good drop in filter.