Cat-Back Exhaust Systems

A cat-back exhaust system replaces the components of the exhaust system from the catalytic converter to the rear of the vehicle, typically including the muffler and tailpipe. These systems improve exhaust flow by reducing back pressure, leading to increased horsepower and torque. Since the catalytic converter is retained, cat-back systems are often street legal and offer a balance between performance gains and compliance with emissions standards. They also enhance exhaust sound without significantly affecting emissions control.

Decat Exhaust Systems

A decat exhaust system removes the catalytic converter entirely, allowing exhaust gases to flow freely with minimal restriction. This dramatically improves engine performance by increasing exhaust flow and reducing engine back pressure, leading to higher horsepower and faster turbo spooling in forced induction engines. However, decat systems significantly increase emissions and are typically not road-legal, making them more suited for off-road or motorsport applications. They also tend to produce a much louder and more aggressive exhaust note.