I was poking around Teh Interwebz the other day reading about air curtains and came across this 2015 video with engineers and designers on the development of the then-new Mustang, including Carl Widmann, aero manager for the Mustang who went on to be the chief engineer on the upcoming Mustang GT500. In particular, the very end of the video has interesting views of the difference in the engine panel and air dam placement between the 2.3L Ecoboost/5.0 GT/GT350--the latter of which does not use an air dam at all. I've never seen a factory air dam shaped like the Ecoboost's, and I didn't think to look under one at the last auto show, so I found this interesting. Enjoy!