Mach wave Mach wave In fluid dynamics, a Mach wave is a pressure wave traveling with the speed of sound caused by a slight change of pressure added to a compressible flow. These weak waves can combine in supersonic flow to become a shock wave if sufficient Mach waves are present at any location. Such a shock wave is called a Mach stem or Mach front. Thus, it is possible to have shockless compression or expansion in a supersonic flow by having the production of Mach waves sufficiently spaced ("cf." isentropic compression in supersonic flows). A Mach wave is the weak limit
Ford Mustang Mach 1 a cold air "snorkel" and a partial Ram Air at speed. 2004 saw only minor cosmetic changes to the Mach 1. 2004 Mach 1s can be identified by bare aluminium finished valve covers, as opposed to the 2003's black finished covers. Outside, 2004 Mach 1's wear 40th anniversary tags ahead of the doors while the 2003 has the traditional Mustang Running Pony and Tri-Color bar. The lone interior change was the deletion of the overhead "cargo net" mounted on the headliner. Despite pre-production rumors, the horsepower and torque ratings were not increased in 2004. Power rating was and . With