8525HKR Hooker Small Block Chevrolet Exhaust Manifolds. Small Block Chevy Universal Exhaust Manifolds, 2.5" Collector, Natural Finish;A smoother, cleaner appearance compared to original exhaust manifolds, while maintaining a factory style look and feel; Made from high silicon-molybdenum ductile iron for high temperature strength plus resistance to oxidation and cracking; Designed with a larger 1 5/8" cross-sectional area and 2 ½ outlets for better air flow and increased performance; Designed for rectangular port heads; Accommodates standard straight and Vortec straight plug head designs for better application coverage ; Includes weld-on flanges for easier downpipe pipe installation (custom downpipe required); Available in natural cast iron or ceramic coated finishes (silver, black and titanium); Includes mounting hardware and gaskets for inlet and outlet flanges. So we have a chance to make it right - we want your repeat business! Check out the official MSD Performance.