The cat (catalytic converter) back exhaust system is one of the most popular and accessible exhaust systems. It’s named ‘cat back’ because it runs from the back end of the catalytic converter all the way to the exhaust tips. The exhaust cat back is made up of a mid-pipe, a muffler, a tail-pipe and exhaust tips. There are also resonators that need to be added and depending on the model of your car, they can be X-pipe, H-pipe and Y-pipe.
There are a few benefits that come from using an exhaust cat back system, such as increased horsepower and fuel efficiency, as well as, an aggressive sound and stunning aesthetic. But to fully grasp these benefits we first must understand the engines combustion cycle.
Internal Combustion Process
The power of your vehicle is generated through a process called internal combustion. It is a process which begins with the intake of air, which is then mixed with the fuel. The mixture is then compressed by a piston and ignited by spark plugs to move the crankshaft which produces power. Afterwords the piston exposes of the leftover gasses out through the exhaust valve. The exposed gasses then continue to flow through the exhaust system until they are released into the atmosphere.
Creating the Best Flow
The piping design and diameter of the pipes are both chosen based on the flow generated from the engine’s combustion cycle. The prime function of the exhaust system is to allow free flow of excess gasses while also giving the appropriate amount of back pressure. This helps ensure an efficient combustion cycle for that specific engine.
Stock exhaust systems are designed to maximise comfort by reducing exhaust noises. On the other hand, performance exhaust cat back systems are designed to maximise power and efficiency. They do this by using bigger pipes and high-flow mufflers to reduce back pressure, which increases horsepower. Also, because of the bigger, broader pipes the engine can expose of the excess gasses more easily, thus resulting in better fuel efficiency.
Apart from performance, cat-back engines also offer a more ‘badass’ vehicle sound and appearance. Because of the reduced pressure on the back and the special mufflers your vehicle will generate a louder, more aggressive sound, compared to a stock exhaust. Some manufacturers even add some glare to their mufflers, such as a chrome tips. This will make the rear of your vehicle look more detailed and taken care of. Cat-back exhausts are also lighter than stock exhausts, this will reduce the overall weight of your vehicle, leading to better acceleration and breaking, as well as lower fuel consumption.