The head pipe is one of the biggest restrictions in your vehicles exhaust system. Pushing air out of the turbocharger wastes power that should be going to the drive wheels. Monster head pipe provides a restriction - free path out of the turbocharger for quicker response, higher boost and more power. The larger diameter increases exhaust flow, producing more torque and horsepower. Head Pipe Kit, Monster Exhaust for use with 2001 - 2004 ChevroletGMC 6.6L