2015 Ford Mustang Headers - Increase performance and improve sound with our Ford Mustang headers. Our 2015 Mustang GT headers are designed with 1-7/8" primary tubes and 3" diameter lead pipes. These 304 stainless steel headers are TIG welded with 3/8" thick flanges and 3" diameter slip fit collectors with merge spikes. You get superior performance with a lifetime guarantee.Available with a variety of options:Choose from our high-flow catalytic converters or off-road pipes. Also choose your connection point: Factory Connect easily mates to the factory connection point (to the factory exhaust), or Performance Connect, to pair with one of our Stainless Works 2015 Ford Mustang exhausts, which retains a full 3" diameter, and doesn't neck down.