Hooker Weld-up kits work great for racers who need to build custom headers when a specific fit tuned Super Competition header is not available. Kits come with mandrel bent one piece primaries, two 5/16" flanges and precision formed collectors incorporating unique long transition to provide better flow. Polished stainless steel NHRA contingency header I.D. tags, gaskets and mounting bolts are also included. Our newest zoomie weld-up kits for Funny Cars and Dragsters are NHRA and IHRA legal and feature 21/2" primaries with double tube design. Popular fuel and alcohol engine header flanges are available separately.