4:1 Headers w/ Y-Pipes, 1-3/4" Primary, 2-1/2" Collector

The Doug Thorley THY-340-C headers and Y-pipes are engineered to enhance the performance of select V8 models. Specifically designed for the 5.3L V8 engine found in the 2006-2009 Chevrolet Impala SS, 2005-2009 Chevrolet Monte Carlo SS, 2005-2008 Pontiac Grand Prix GXP, and 2007-2009 Buick Lacrosse, these headers aim to extract more power. Constructed from robust 14-gauge steel, these headers feature a 4:1 design with 1-3/4" primary tubes and a 2-1/2" collector. They are finished with a silver ceramic coating, which helps to reduce under-hood temperatures and provides environmental protection. The kit includes bolts, and the Y-pipe has a 2-1/2" inlet that connects to a 3" outlet, requiring welding for installation. The product is 100% American-made and includes a limited lifetime warranty. Installation notes specify that the Y-pipe outlet must be welded to the exhaust inlet. Crucially, these headers are NOT legal for street use on pollution-controlled vehicles and CANNOT be shipped to California due to emissions regulations.