1 3/4" 2001-2004 C5 Corvette headers and 3" center section with x pipe-for off road use only-no converters. Bolt on installation with no cutting and welding required. Manufactured from 304 Stainless, the headers feature 3/8" thick, CNC laser cut flanges, and CNC mandrel bent 1 3/4" primary tubes. The headers are completely tig welded together, and have the AIR tubes and Oxygen sensors installed. The headers have shown gains of 40+ rear wheel horsepower on highly modified engines. Also available as part #C5LS103 as headers only, or C5LS103CAT with 3" high flow cats and x pipe.