Roush Performance Pac Level 2 GT 2015-2017



  • Significant Power Increases
  • Easy Installation
  • Revised Intake Design
  • 2.5" Axle Back
MSRP $1,227.00
You save $47.01

Roush Level 2 Performance Pac for 2015, 2016 and 2017 GT Mustangs.

The Roush Level 2 Performance Pac for the 2015-2017 Mustang GT (421997) adds an exceptional 29 RWHP and 36 lb-ft. of torque to your stock Coyote 5.0L V8. For increased performance without excessive work, this is the kit for you. Additional perks include a sportier feeling and sounding vehicle. These modifications are easy to make, and the benefits behind the wheel are obvious.

Features and Benefits:
- Increased engine performance of 29 RWHP and 36 ft-lb RWTQ over stock!
- Package includes a “Flash Voucher Card” containing the voucher code & voucher family necessary to recalibrate vehicle
- Cold Air Intake is CAD designed for optimized hood sealing to keep out heat and gain maximum performance
- Includes a high flow, high capacity, washable and reusable performance air filter (does NOT require oiling)
- Increased torque and horsepower across the entire RPM range
- Improved throttle mapping lends a more “aggressive” feel to the 5.0L Coyote engine
- Calibration optimized and designed by Roush engineers
- Includes all necessary hardware
- Made in the USA

In addition to improved horsepower and torque, our kit also provides improved boost and throttle mapping that will lend a “sportier” feel right off idle to provide amazing drivability improvements all through the power band. Between the revised cold air kit, premium 2.5” axle-back exhaust, and remapped ECU calibration, Roush takes the guesswork out of performance. These easy enhancements result in serious gains!

Tech Tip: The Roush calibration in our Performance Pac is easily programmed into the ECU of the vehicle via an industry standard J2534 Dongle tool (NOT Included) & our free Roush Diagnostic Tool (RDT) software (note: dealer service charges may apply). Most Roush Performance authorized dealers, should they be equipped with the proper tool, can complete the calibration process in under an hour.

Please Note:
- Powertrain calibration is developed and supported for U.S. and Canadian vehicles ONLY.
- Premium fuel, 91 octane or higher, is required.
- Performance Pac calibration is NOT designed to be compatible with other aftermarket powertrain components.
- Flash card voucher is final sale and is NOT returnable.

This Kit Includes:
- Cold air intake kit with re-usable premium air filter
- Flash voucher card with voucher code and voucher family
- 304 stainless steel 2.5" axle-back exhaust kit with mufflers
- Dual 4" chrome-plated tips
- Also includes all necessary installation hardware

ATTENTION: Updated Operating System Requirements for the Roush Diagnostic Tool (RDT). The Technical Service Bulletin TSB 21-0802-AA has been issued by Roush. As of September 10, 2021, Windows 10 will be the ONLY operating system that will be supported by Roush Performance for the Roush Diagnostic Tool (RDT). Older operating systems, such as Windows 7 or earlier Windows operating systems (XP, Vista, etc.), will not be supported. All instances of RDT will need to be updated to the most current release. All previous versions of RDT will NOT be able to program or configure modules due to a software license time-out.

The updated minimum recommended PC Hardware Configuration will be:
- Processor minimum: 2.4 gigahertz (GHz) or greater Intel I5/I7 Dual Core
- Memory minimum: 4 gigabyte (GB) RAM or greater
- Windows 10
- Microsoft .NET Framework 4.0 or later

California Residents: Proposition 65 Warning

Note: This item is not CARB (California Air Resource Board) exempt and is not legal for sale or use in the state of California.

Installation Difficulty


Intermediate skill is required for this installation.

Vehicle Fitment

This product will fit the following Mustang years:

Only registered users can ask/answer questions. Please sign in or create an account.
Write Your Own Review
Only registered users can write reviews. Please sign in or create an account.