50 States Emissions Legal (E.O. D-701-34). GM 6.6L Duramax High-Flow Exhaust Manifolds and Up-Pipes Kits PPE High-Flow Manifolds are made from cast, high-sil moly. The PPE Up-Pipe bellows are internally sleeved, made from aircraft-grade 304 stainless steel, and designed with increased inner diameter for higher flow. The entire Manifold and Up-Pipe exhaust system are designed to maximize power and flow characteristics, lower exhaust gas temperatures (EGTs) and accelerate turbo spool-up while increasing power, fuel economy, and maintaining reliability. High-Flow Exhaust Manifolds Ceramic coating is available as an option for High-Flow Exhaust Manifolds. Ceramic coating was pioneered by the military and defense industries. Now considered a standard in high-performance applications like Formula 1 and military jet aircraft. This same process is available to you - today. The Ceramic-Coating option enhances the existing benefits of the PPE Manifolds and Up-Pipes Kit which is specifically designed to maximize power and flow characteristics. Ceramic coating creates a thermal barrier and doesn't absorb heat as quickly as raw metal. This reduces the thermal cycle and surface temperature. The ceramic coating promotes even greater flow, which means lower exhaust gas temperatures (EGTs). Ceramic coating also offers long-lasting protection against moisture, road salts, oil, fuel, and other corrosive chemicals. Plus, ceramic coating keeps your PPE Manifolds looking great - for a long, long time. 304 Stainless Steel Up-Pipes Kit Choose the Ceramic Coating Option added to your PPE Manifolds and upgrade your GM 6.6L Duramax with the superior combination of PPE Manifolds with 304 Stainless Steel Up-Pipes Kit. Complete your upgrade with a PPE Stainless 3 Inch, 304 Steel Down Pipe. LML model requires modification on upper control arm bushing heat shield. Up-Pipe configuration may vary depending on your model.

Important:
The factory downpipe (2001-2004 LB7 only) does not fit aftermarket manifolds and up-pipes.