The difference is that the dual exhaust system has two exhaust systems on one vehicle. Meaning, when modifying your exhaust, never start from the front of your turbocharged vehicle with a downpipe or with headers on your naturally-aspirated platform, you will create a bottleneck in the flow. By starting with a cat-back first, your exhaust gases will flow more freely if the rest of your system is stock.

To maintain catalyst efficiency, the air–fuel ratio must stay close to stoichiometric and not remain rich or lean for too long. All of Milltek's performance exhaust systems are manufactured from T304L stainless-steel