The Ford Mustang GT already offers a lot of performance bang for the buck, but Ford Performance Parts is giving owners of 2015-2017 models more go-fast options with three new Power Packs. The upgrades are emissions-legal and add as much as 37 peak horsepower.

With every Power Pack, owners will receive 50-state-legal Ford Performance calibrations that enhance throttle response and a ProCal tool that requires a laptop and internet connection for installation. The calibrations are available for both manual and automatic transmissions, but a "no-lift shift strategy" is offered for manual models. Automatic-equipped cars get an optimized performance shift schedule. The Power Packs require 91 octane fuel or higher and are currently only offered for North American-spec Mustang GT models.

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Power Pack 1, which will be available starting August 1 at a price of $539, includes a K&N high-flow air filter and nets peak gains of 13 hp and 16 lb-ft of torque over the stock GT's 435 hp and 400 lb-ft. At 1,500 rpm, torque improves by 40 lb-ft. For $949, Power Pack 2 upgrades to a GT350 cold air intake and 87-mm throttle body for peak gains of 21 hp and 24 lb-ft. Torque at 1,500 rpm also increases by 40 lb-ft. The GT350 hardware and adapter are available as separate upgrades without the calibration, priced at $539, and come with an industry-exclusive open air filter with a California Air Resources Board (CARB) EO exemption number. Power Pack 2 will be available beginning in September.

Finally, Power Pack 3 includes the GT350 cold air intake, larger throttle body, and a GT350 intake manifold. Those bits grant an extra 37 hp and 51 lb-ft at peak, and 60 more horsepower at 7,500 rpm. The manifold includes a CARB EO number. How much will those additional ponies cost you when Power Pack 3 arrives in October? A whopping $2,395.

The law prohibits the upgrades from being installed prior to the sale of a new car, so if you want the extra horsepower you'll need to do it after you leave the dealer lot.

Source: Ford Performance