Taken from Mustang6G."Our photographers have caught new photos and video footage of the upcoming 2019 GT500 Mustang out testing near Dearborn.The video gives us our clearest audio yet of the supercharged 5.2-liter cross plane crank engine being tested for the 2019 GT500. This is an early (M1-build) prototype with underbody and powertrain changes only. With the exception of the front end (which affects cooling), the M-1 builds do not wear representative bodies that would incorporate some of the exterior changes of the 2018+ Mustang mid-cycle refresh.Interestingly, this prototype also shows what appears to be a roll cage visible through the rear quarter window.We showed this to some of our inside sources and they tell us the 2019 GT500 will be an absolute beast, potentially making over 800 horsepower and featuring a dual clutch transmission derived from the Ford GT's 7-speed DCT. A manual transmission was also being tested but it is still unclear whether the option will make it to production."We're told to expect 20-inch wheels and tires (315 wide at the rear) with massive true 2-piece brake rotors. It will also have composite springs and "other lightweight chassis components."