Hey everyone, I have a 2016 Mustang GT and want to install O/R X-pipe. I know if I install an O2 sensor spacer/extender, it will prevent a CEL/DTC, but Im unsure if I'd still need a tune even if there's no CEL/DTC? I appreciate any and all advice. Thanks

 

The cats are part of the stock headers, I don't think you can eliminate them without swapping in a set of long tube headers. Then you can eliminate the cats with the correct (no cat) connector, and add your X pipe and a custom tune. That said, You can replace the stock center resonator with an X or H pipe with minimal effort and no tune.