In layman’s terms, a catback exhaust system provides a smoother, more streamlined path for exhaust gases to exit your car, allowing your engine to work more efficiently. When catalytic converters were first introduced, most vehicles used carburetors that provided a relatively rich air-fuel ratio. Oxygen (O2) levels in the exhaust stream were therefore generally insufficient for the catalytic reaction to occur efficiently.

Cat-back exhaust systems will include any pipes that run from the catalytic converter to the muffler, the muffler itself, any pipes that may run from the muffler to the exhaust tips, and the exhaust tips themselves. Some cat-back exhaust systems have a muffler 2016 cummins delete kit, which means no muffler is included. This is typically found on vehicles that function primarily for off-road use