There is a common misconception that the cat-back exhaust replaces the catalytic converter. That is not true at all. Cat-back exhausts are simply aftermarket exhaust systems containing parts that attach to the converter.
To put it more precisely, no, a cat-back exhaust does not replace a catalytic converter. However, it is going to replace all of the components that are located at the back of the catalytic converter.
You can consider the cat-back as an upgrade to the existing exhaust system. Auto owners who are not happy with their stock options often opt for it.
I will go in-depth about cat-back exhausts throughout the article. I will also address why they are not a replacement for catalytic converters. Let’s begin!

Why Cat Back Exhaust Cannot Replace Catalytic Converters?
It is impossible for the cat-back exhaust to replace a catalytic converter because it has attached parts to the cat.
Cat-back systems contain a variety of components, such as mufflers and tailpipes. They form the exhaust system and are connected to the catalytic converter.
If you remove the converter, none of the cat-back’s components will work. Hence, catalytic converters are not replaceable by cat-back exhausts.
What Is A Cat Back Exhaust?
The cat-back exhaust system consists of various components ranging from the back end of the catalytic converter to the tip of the exhaust. Hence, the name includes ‘cat’ and ‘back,’ referring to the backside of the catalytic converter.
If you have trouble understanding the term, just remember it refers to an aftermarket exhaust system.
It goes without saying that a stock exhaust will not satisfy the needs of a motorhead seeking high performance.
This is where a cat-back exhaust shines the brightest. It unleashes a vehicle’s full potential along with many other advantages.
Advantages of Cat Back Exhausts
Didn’t I say earlier that the cat back system has several advantages? It wasn’t a mistake.
As it turns out, cat-back exhausts offer quite a few advantages over conventional exhaust systems. Let’s take a closer look at them.
Fuel Efficiency
Purchasing a cat-back system requires a hefty budget. However, over time, you are likely to recoup that money. An exhaust like the Borla cat-back system ensures excellent fuel economy, saving you plenty of bucks in the long run.
It is fairly large in diameter. Moreover, you will experience a reduction in back pressure as well. All of this contributes to less engine stress.
As a result, your vehicle performs more efficiently, especially on freeways.
High-end Materials
I can assure you that manufacturers put less emphasis on high-quality materials for exhausts. They continuously look for ways to cut costs; unfortunately, the exhaust has to take the hit.
Exhaust systems are commonly made of uncoated steel. It is highly susceptible to rust. You won’t get high performance from rusted exhausts.
Thankfully, cat-backs are available in stainless steel or aluminized steel. It is coated in a way that prevents rust effectively.
Enhanced Torque and Horsepower
Here comes the advantage you were probably most excited about.
Due to the large diameter of a cat-back exhaust, the flow of exhaust improves dramatically. This, in turn, decreases the amount of back pressure. Thus, an engine can breathe more freely, producing greater torque as well as horsepower.
Please take note that horsepower gains are not always noticeable. To get the most out of your cat-back, make sure you have a high-end catalytic converter.
Related: Does Removing Catalytic Converter Increase Fuel Consumption?
Upgraded Sound Quality
With a cat-back exhaust, a vehicle’s sound will improve depending on its muffler.
In the case of a glass pack muffler, the car’s sound will be more aggressive and loud.
Another type of muffler that cat-back exhausts use is a straight-through muffler. It is capable of absorbing sound, resulting in low noise levels. The sound is also going to be deep yet pleasant.
Effortless Installation
Several exhaust systems are available on the market, but none are easy to install. However, since the cat-back system usually fits a specific series/model of cars, the installation is usually hassle-free.
All you need to do is bolt in each part at the appropriate location. Even a beginner won’t have any problems with this.
Does A Cat Back Exhaust System Include A Catalytic Converter?
No, the cat-back exhaust system does not include a catalytic converter. However, you have to remember that the cat-back exhaust’s components are all connected to a catalytic converter.
There are different kinds of cat-back exhausts, each with its own set of parts. Nevertheless, none of the models will come with a cat.
What Does Cat Back Exhausts Include?
Okay, so it appears you won’t get a catalytic converter with the cat-back. Then what would it include?
To discover that, take a look at the complete list of components below.
- Tailpipe
- Outlet pipe leading out of the catalytic converter
- Exhaust tips
- Muffler
Almost no cat-back exhaust is complete without these components.
In addition, some advanced cat-back systems may be equipped with pipes other than those mentioned above. Let’s see them.
- X-pipe
- H-pipe
- Mid-pipe
- Y-pipe
Do You Need A Catalytic Converter With A Cat Back Exhaust?
You do need a catalytic converter with the cat-back exhaust since the parts of the exhaust must be attached to the converter.
However, a cat-back exhaust does not feature a catalytic converter. You either need to purchase one or have one already installed on your car.
Read Also: Do You Need a Catalytic Converter to Pass Inspection?
Does A Cat Back Exhaust Remove The Catalytic Converter?
No, the cat-back exhaust is not going to remove the catalytic converter. What it removes are the components residing at the rear of the converter. Among them are the tailpipe, muffler, outlet pipe, etc.
All of these parts are already in your vehicle. The cat-back replaces them all with better upgrades to provide increased airflow and performance.
To Sum Up
As I stated in the article, a cat exhaust is not meant to replace a catalytic converter. Instead, it replaces numerous parts associated with the cat.
In order for the cat-back system to function, catalytic converters are essential. This explains why replacing the cat with cat-back exhausts doesn’t make sense.
If you would like to read more articles about catalytic converters, check out this comparison of high-flow cats and no cats.