Flowtech Headers are the perfect combination of performance, quality, and value. This header fits the popular 2011-14 Ford Mustang 5.0L V8 Coyote engine platform. This header features 1-3/4 primary tubes and a 2-3/4 collector for increased exhaust flow for increasing performance, improving throttle response and providing a broad torque curve. This header accommodates all emission control devices and reuses the factory header gaskets and hardware. Features: Heavy duty 16-gauge mild steel tubing for increased strength and durability Mandrel-bent tubing provide consistent tubing diameter for smooth flow and increased exhaust velocity 1-3/4 primary tube diameter for increased exhaust flow increasing performance and improving throttle response OE style 2-3/4 collector connects to factory exhaust head pipe TIG-welded, machined 7/16 header flange for a leak-free seal and maximum strength Accommodates all factory OE components Available in a raw or polished finishes Headers are a must if you are using a cold air intake, cat-back exhaust system or tuner Retains factory O2 sensors and catalytic converters