aFe Dyno Results: During dyno-testing, aFe's down-pipe produced max gains of: +16 HP and +17 ft./lbs. torque (2015 Mustang I4 2.3L).
Tuning Required: This cat-back kit will require a custom tune to avoid a check engine light, while making proper levels of power and avoiding engine damage.
Down-Pipes Available: Sold separately, aFe also offers a 3" diameter performance down-pipe to complete your aggressive EcoBoost build. Choose either their "Street" - catted system (part#: 48-33017-HC).
This kit may not meet emissions requirements in your area. Please verify before ordering.
Coupes Only: aFe's cat-back exhaust kit will only fit 2015-2023 Mustang EcoBoost Coupes, and will not fit convertibles.
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WARNING: Cancer and Reproductive Harm
This product can expose you to chemicals including those known to the State of California to cause cancer and birth defects or other reproductive harm.
For more information, visit [www.p65warnings.ca.gov](https://www.p65warnings.ca.gov).