SLP's original Tuned-Length Long-Tube Headers use patent-pending tuned-length design to optimize exhaust scavenging for phenomenal power increases. Gains of up to 41 horsepower and 58 lb.-ft. of torque are possible, depending on your application! These headers are constructed from 409 stainless steel and feature 1-3/4" primary tubes flowing into a 3" 4-into-1 collector. They're fully compatible with all stock emissions-control equipment and use OEM flanges for a perfect fit and proper bolt retention. Includes matching Y-pipe. NOTES: Requires Installation Kit #30054. Use with Catalytic Converters (Part #31037). Headers reduce ground clearance by approximately 1-1/2 inches. SLP headers will not fit automatic transmission-equipped convertibles. Not legal for use on pollution-controlled motor vehicles. SLP TUNED-LENGTH LONG-TUBE F-BODY HEADERS: Reduce 1/4-mile ETs by up to 5 tenths of a second and increase trap speeds by as much as 5 mph. Offer bolt-on installation. Are compatible with all factory emissions equipment. Feature .055" wall-thickness 409 stainless steel for long life. Are mandrel bent to maximize flow. Use Jet-Hot's polished aluminum-ceramic thermal-barrier coating (interior and exterior surfaces) to keep heat in, exhaust velocity up, and under-hood temperatures down. Are covered by SLP's Performance Guarantee and Limited Lifetime Warranty.