Speed Engineering 1999-2006 Silverado & Sierra Longtube Headers
Speed Engineering Silverado, Sierra and full-size SUV longtube headers use mandrel-bent, TIG-welded natural 304 stainless steel tubing, merge spikes, CNC-machined flanges and 3-inch collectors. Choose 1 3/4-inch (25-1012), 1 7/8-inch (25-1011), or 2-inch (25-1077) primaries, with compatible connection-pipe and SMG upgrade selections.
Standard applications: 1999-2006 Chevrolet Silverado, Tahoe, Suburban and Avalanche; GMC Sierra and Yukon; and 2002-2006 Cadillac Escalade/EXT, subject to drivetrain, chassis and exhaust restrictions.
Additional source application for 25-1012 and 25-1011 only: Speed Engineering also publishes these exact two SKUs for 1988-1998 Chevrolet/GMC K1500 OBS 4WD 1/2-ton LS swaps. This use is 4WD-only, does not fit 2WD, and may require Y-pipe/exhaust modification. The 2-inch 25-1077 option is not represented by Speed Engineering for that K1500 application.
SMG Ceramic Plug Wire Upgrade
SMG 9070C 8mm ceramic plug wires use heat-resistant ceramic boots that will not melt against hot header tubes like conventional boots can. They are the only plug wires used on SMG in-house header builds. SMG LS MLS gasket combinations are also available. Race-use product.
Processing & Shipping Overview
Processing occurs before shipping.
Most in-stock items typically process within 2–3 business days before shipment or pickup. Expedited shipping options affect transit time after an order ships and do not speed up processing.
Made-to-order, special-order, vendor drop-ship, and freight items require additional processing time before shipping. Any extended lead times will be noted on the product page when applicable.
For the most up-to-date order status or lead time questions, please contact sales@smgspeed.com or use live chat during business hours.