Our products highperformance automotive components for racing, street and offroad use. We always work towards to fulfill the requirements of our end users. Features. High quality construction and durability. Variety of styles for every type of accessory. Headers. IMCAUMP Stock Car. 15/8 to 13/4 in Primary. 3 in Collector. Steel. Black Paint. Small Block ChevySpecifications. Finish Black. Material Steel. Collector 3. Size 1.62 to 1.75