Cat-Back Exhaust Systems

More sound, less back pressure or a different look at the rear? A cat-back system replaces the exhaust from the catalytic converter back, meaning mid-pipes, mufflers and tailpipe tips. This category is for you if you want to change the sound and flow of your project without touching the catalytic converter or the exhaust manifold.

How to choose a cat-back exhaust

A cat-back system can provide freer flow and a different sound than the stock exhaust. How noticeable it is depends on the engine, pipe routing and mufflers. Vehicle-specific systems are adapted to the hangers and pipe routing of a particular model, e.g. the Cobb system for the Evo X or the Revel exhaust for the Mazda 6. You will find them under vehicle-specific cat-back systems. Universal cat-back kits typically require fitting and welding, but give you freedom in projects where no ready-made solution exists.

• Pipe diameter: It should match the engine's power output and any boost pressure. Bigger pipes are not automatically better and can change both sound and response.
• Sound level: The number and type of mufflers determine how loud the system sounds and whether it can cause drone at constant speed.
• Tips: Single, dual or quad tips must match the cutouts in the bumper.
• Material: Steel type and wall thickness affect durability and weight.

The category includes brands such as Magnaflow, Borla, Gibson, aFe and AWE Tuning. If you only want to replace the rear section, an axle-back exhaust is a smaller modification, while a turbo-back exhaust on turbocharged cars also includes the pipe from the turbo. Gaskets, clamps and rubber hangers can be found among our exhaust installation kits. Worn rubber hangers can cause rattling and should be replaced during installation.

Frequently asked questions

What is the difference between cat-back and axle-back?

Cat-back replaces everything from the catalytic converter back, typically mid-pipes, mufflers and tips. Axle-back only replaces the section behind the rear axle, usually the rear muffler and the tips, so the change in sound and flow is typically smaller.

Can a cat-back exhaust pass vehicle inspection?

It depends on the product and the car. Sound level and any E-mark must be checked for the specific part number. Even a marked exhaust can be rejected if the sound level on your car exceeds the permitted limit.

Does installing a cat-back require welding?

Vehicle-specific systems are typically installed with clamps or flanges in the original hangers. Universal kits often require cutting and welding. Always check that the pipes do not touch the underbody or heat shields once the system is tightened.