Every current Ford Mustang except for the Bullitt is offered with some kind of handling package. The GT serves up the optional Performance Packages in Level 1 and Level 2 trim, the Shelby GT350 puts a Handling Package on the menu, and the top-drawer Shelby GT500 provides the choice of a Handling Pack or a Carbon Fiber Track Pack. The new 2021 Mustang Mach 1 replaces the Bullitt, correcting the Bullitt's omission of sharper circuit chops by offering its own Handling Package. As with everything else about the Mach 1, the cost-extra bits come from a combination of the GT below and Shelbys above. The option can only be ordered with the six-speed Tremec manual gearbox, a diversion from the 1969 Mach 1 that offered a three-speed automatic across the range. But enthusiasts are pleased.
Starting at the front, there's a new two-stage splitter similar to the one on the Mustang GT PP2 creating more downforce, and new front wheel lip moldings. Under the skin, the coupe picks up the front adjustable strut top mounts from the GT350. In back, the rear wing is upgraded from the demure blade on the standard car to a low-gloss swing spoiler and Gurney flap from the GT500. The rear tire spats behind the back wheels come from the monstrous GT500 as well.
The base car fits 19-inch Magnum 500 wheels that are 9.5 inches wide in front, 10 inches wide in back, shod in Michelin Pilot Sport 4S tires. The Handling Package adds a touch of thickness, slipping on a set of 19-inch Magnum 500 wheels grown to 10.5 inches in front and 11 inches in back, the same size as the upgrade that comes with the Mustang GT PP2. The wider rims wear grabbier Pilot Sport Cup 2 rubber swiped from the GT350R. That means the complex and comely star-pattern 20-inch wheels aren't included, sadly.
Revisions appended to the standard Mach 1, like the standard front splitter and longer underbelly pan with airfoils, collectively provide the limited-edition model 22% more downforce than the Mustang GT Performance Package Level 1 achieves. Checking the box for the Mach 1's Handling Package takes that multiplication to 150% over the GT PP1.
As we're still awaiting pricing for the Mach 1 itself, we don't know the cost of the the Handling Package. The Performance Pack Level 2 for the Mustang GT costs $6,500, but the Mach 1 already comes equipped with many of those package improvements. The GT350 Handling Package costs just $850, but it bundles just two items — the adjustable strut top mounts in front and Gurney flap out back. Somewhere around the middle of those two numbers sounds right to us for the Mach 1.