JBA Headers Full-Length w/2.5" Collector (2005+ Mustang GT) These JBA headers take full advantage of the redesigned chassis and engine of the 2005 Ford Mustang. The trick D port aluminum heads on the 4.6L 3v can breathe easier through JBA's 1.625 mandrel-bent stainless steel primaries freeing up massive amounts of horsepower and torque. JBA's one-piece .375 CNC laser-cut flanges make a tight and durable seal for trouble-free performance. The pipes terminate in a 9 long collector that houses JBA's patented Firecone® merge device for enhanced scavenging of exhaust gasses. These headers fit perfectly inside the frame with no loss in ground clearance. •Thick 3/8inch Header Flange •Patented JBA Firecone merge collector •Mandrel-bent 409 stainless steel primary tubes •JBA Slip-fit Collector •Limited Lifetime Warranty Direct replacement of the stock exhaust manifolds, header bolts up to the existing stock Y-Pipe/Crossover pipe. Installation requires modification to exhaust system. Takes between 3 And 6 hours depending on application. All hardware, gaskets, and instructions included. For Off Road Use Only - This Item Is Not Emissions Legal