Abstract: An improved ram air charge heat exchanger ducting system, is disclosed comprising an elongated, hollow header tank, having a generally rectangular opening therein for engagement to a header sheet of a heat exchanger core. The hollow header tank is of increasing depth from a closed end to an outlet end, and the outlet comprises an attachment ridge having a mounting surface arranged in a plane at an angle to the plane of the header mounting surface. A duct inlet has a mounting surface configured to generally mate with the mounting surface of the header outlet and, means are provided to removably attach the duct to the header outlet. This system allows variety in attachment for multiple automotive environments.