We last saw Jack Roush take delivery of his brand-new 2017 Ford GT, and just a week later he's announcing the "most powerful American pre-titled car ever built." It's called the Roush P-51 Mustang, and it is based on a standard Mustang GT. Roush adds a Phase 2, 2.3-liter Eaton TVS supercharger to get 727 horsepower out of the 5.0-liter Coyote V8. This immense power can be routed to a six-speed manual or automatic transmission, and there are plenty of other upgrades included in the package.

The P-51 gets the Roush TrakPak components, including a 3-way adjustable coilover suspension and lightweight black forged wheels by Weld wrapped with Continental ExtremeContact Sport tires. Manual-equipped cars also get PFC 2-piece rotors and updated friction pads. On the interior, the car is given Amaretto Tuscany leather seating with matching door inserts. This luxurious leather is complemented by a unique P-51 gauge logo, red shifter ball, Roush Performance pedals, and a P-51 interior plaque. To ensure plenty of aural pleasure, there's an active exhaust system with three profiles as well as a custom mode that can be tuned via a phone app.

The exterior sets itself apart from a normal Mustang with a carbon rear deck lid spoiler, a new carbon fiber front splitter with support brackets, unique custom paint on the hood, front grille ambient lighting, and custom badges. All of this performance is backed by a three-year, 36,000 mile warranty. It is pretty expensive at $42,500 plus the donor car. Assuming that the package can be put on a base Mustang GT, total cost would be around $76,000. That is about $14,000 more than a Dodge Challenger Hellcat, although the P-51 does have more power and a lighter curb weight. Until Shelby reveals a new GT500, this Roush P-51 is the king of Mustangs right now.