Flowmaster Flow FX Cat-Back Exhaust SystemFlowmaster introduces our Flow FX cat back exhaust system for the 2021 2026 Ford Bronco 2 door with the 2. 3 or 2. 7 liter engine. This system uses a Flow FX style muffler for a deep exhaust tone and increased performance. Maximum dyno gains of 12 hp and 13 lb ft were measured at the rear wheels. 3. 00 inch mandrel bent 409 stainless steel tubing is used to maximize exhaust flow and durability. This step up from the factory pipe size will help