Cams and Pistons I can agree with, PnP eh I dunno about that. I'm not trying to start an argument, but how can you say the engine wouldn't be faster with physical changes??? Different cams means a longer or shorter duration of the valves opening, direct effect to performance. A change in CR, direct effect to performance. Granted you do need to tune to maximize the changes made, but to say simply changing the parts won't benefit the performance is naive. Having said that I thank you for your input.