I/H/E/ = intake/header/exhaust. And don't waste your money on it until you have decided for sure whether or not you are going to go turbo or get a different engine or keep your current engine and build it. I/H/E is basically like spending $1,000 to make your car sound fast..that's about it. You wont' start noticing gains until you do some REAL internal work to your engine. So save your $$ and buy an H22 or other engine swap and start off with a 175-200HP base to build off of. Otherwise you are wasting your $$.