ROUSH Performance's Resonator Delete Y-Pipe is a quick and affordable way to eliminate your factory resonator to get deep, aggressive and race-inspired sound. Our Y-Pipe increases flow through your 2015-2023 Mustang I4 exhaust system for maximum horsepower and torque. The 2.5-inch Y-Pipe assembly is made from high-grade mandrel-bent 304 stainless steel to ensure maximum flow with less back pressure and long-lasting durability. The system is designed and engineered using OEM vehicle CAD data to ensure perfect fit. ROUSH Performance recommends checking your local noise ordinance levels prior to purchase. Pair with our axle back kits to take your Mustang to the next level!2015-2023 Mustang 3.7L ROUSH V6 and 2.3L Ecoboost Exhaust Kit (#421837)