aFe is proud to introduce an all new Twisted Steel long tube catted headers/Connection Pipes combo for the 2011-2014 Dodge Challenger SRT-8 with V8-6.4L engine. "Improve your Challengers horsepower" with these full length headers and connection pipes. In testing, this system resulted in gains up to +19 horsepower and +17 lbs. x ft. of torque, as measured on our in-house dyno. Designed to replace the extremely restrictive exhaust manifold, the performance Twisted Steel long-tube headers are constructed of 1-7/8", 16 gauge, mandrel-bent, 304 stainless steel tubing for strength and durability. A 4-to-1 formed collector is used on the headers to decrease turbulence and increase exhaust velocity for maximum performance. The high-flowing connection pipes are designed using 48-state legal 200 cell catalytic converters and 3" mandrel-bent, 304 stainless steel tubing for optimum flow resulting in added horse power and torque. This system is designed to fit as a combo with all necessary hardware for a hassle-free installation.