Stainless Steel Exhaust Header 63-81 BBC Chevy Big Block 396/402/427/454 V8 Fits: 1963-1981 BBC Chevy Big Block 396/402/427/454Ci V8 For: Chevy Bel Air/Camaro/Caprice/El Camino/Impala/Laguna/Malibu/ Tube Diameter: 1.75". Collector Size: 3.00" Flanged Connection. TIG Weld & Polished Stainless Steel Mandrel-Bent For Maximum Performance