Originally designed for Ken Block's Gymkhana 1 2006 STI. See it in action here:
This exhaust was designed for Ken Block and the Gymkhana Cars, but was originally inspired by the Crawford Performance Time Attack Race Car with one main reason behind this system, to be heard. Crawford Performance came up with an exhaust design that adds reverberation to the sound. The result is a doubling of the sound amplitude in effort to make the exhaust audible over the rest of the race track. It produces a loud, but deep sounding rumble, unlike anything on the market.
Made from 304 stainless steel, and hand fabricated in-house. 3 inch body to 4.5 inch tip.