The BBK full-length headers are built with the same 13⁄4-inch CNC mandrel bent tubing and 3⁄8-inch flanges. These can also be ordered in three different finishes. We decided to use the stainless versions for this Camaro. In this install, we will be coupling the full lengths to a single high-flow cat per side. BBK also offers an X-pipe that eliminates the cats altogether, but we wanted to see the potential these headers have while still running through at least one cat.