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Flowmaster 817750 American Thunder ® Cat Back System Ford Mustang Ecoboost

Regular price $857.95 USD
Regular price $1,143.93 USD Sale price $857.95 USD
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Shipping calculated at checkout.
The classic sound of a Flowmaster chambered exhaust, our American Thunder® Series features mufflers tuned to deliver more power, torque, throttle response and mileage. Best of all, these exhaust systems take sedate vehicles and deliver that great performance tone especially designed for muscle car and truck fans. American Thunder is the most authentic Flowmaster muffler sound we offer.

Sound Level: Aggressive/ Moderate
Type: Cat-Back
Exhaust Type: Single
Outlet Type: Dual
Exit Position: Rear Exit
Material: Stainless Steel
Diameter (IN): 2-1/4 Inch
Includes Exhaust Tip: Yes
Exhaust Tip Style: 4 Inch Round Double Wall Angle-Cut
Exhaust Tip Material: Stainless Steel
Includes Muffler: Yes
Muffler Quantity: 2
Includes Exhaust Pipe Muffler Delete: No
Muffler Configuration: Single Inlet, Single Outlet
Muffler Brand: Outlaw
Includes Hardware: Yes
Required Welding: No
Estimated Install Time (Hours): 2



  • Stainless Steel Construction
  • Dyno Tuned For Maximum Performance
  • Race Proven Outlaw Muffler Technology
  • Limited Lifetime Warranty
  • Fitment 2015-2021 Ford Mustang Ecoboost
  • Exhaust System Kit; American Thunder ® Cat Back System; 409 Stainless Steel; 2-1/4 Inch Pipe Diameter To 3 Inch Pipe Diameter; With Mufflers; Single Exhaust With Dual Exit; Dual Split Rear Exit; 4 Inch Double Wall Polished Stainless Steel Tips

 Prop 65 WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. For more information go to