The PPE High-Flow Exhaust Manifolds with Up-Pipes for your 02-04 GM 6.6L Duramax LB7 increase exhaust flow by 20 percent and are 50 state emissions legal. Designed to outlast your truck the manifolds are made from high-quality cast iron and the up pipes are made from stainless steel. Plus the aircraft grade Up-Pipe bellows are high-flow, internally sleeved, and have an increased inner diameter.

Features:
•CARB E.O. D-701-1
•Significant reduction in exhaust back pressure>
•Free flowing Stainless Steel Inner Liner Bellows
•Stainless Steel 11-gauge .120-inch wall diameter Up-Pipes
•Built in bosses, pre-drilled and tapped 1/8" NPT for EGT gauge