The Z is not as simple as a small block Chevy - so when you mod...you had better be sure of what you or doing or have access to someone who does. I have seen a local story unfold of a passionate Z owner try to save a buck doing a major modification with a self ordained Z expert - only to have the engine blow due to an improperly installed timing belt and tensioner. To Ash's point - they are machines - in some areas - very precise machines and the craftsmanship required to make that machine work at the specifications greater than it was originally intended for comes at a price.