SuperMAXX Stainless Long Tube Headers are an excellent way to bolt on 15 Hp and 24 Ft. Lbs. of Tq. to your 2007 – 2010 Mustang Shelby GT500. Although a tune is recommended, these power gains were before the tune! A power tune could add another 20-25 Hp. 100% Stainless Steel construction with a Limited Lifetime Warranty makes the SuperMAXX header second to none. 1.875” primary tubes and a 3.00” collector make a great combination for stock engines and/or upgraded power plants. Fits with automatic or manual transmissions and takes about 5-7 hours to install. Comes complete with detailed, full color instruction manual for easy installation. O2 Extension cables, triple layer stainless steel gaskets, header bolts and all installation hardware are included. Designed for use with Dynatech intermediate sections (part numbers 722-54320, 722-54330, 722-64320 or 722-64330)