Motor State Distributing has set the pace for highperformance automotive components for racing, street and offroad use. Features. Street Stock Headers for SB Chevy 1.62 in. to 1.75 in. Tube 3 x 8 in. Collectors. High quality construction and durability. Variety of styles for every type of accessoryCompatibility. Small Block Chevy 1.62 in. to 1.75 in. Tube 3 x 8 in. CollectorsSpecifications. Size 1.62 in.