Catback Exhausts 101: Horsepower, Sound, Tuning & Legal

By February 5, 2022Exhaust

The Catback exhaust is a great way to improve your car’s horsepower and sound –  while still being legal in many US states (provided that it’s within sound limits).

Personally, I have tested the cat-back exhaust on a 2004 Toyota Tundra, and I must say I noticed a massive difference in the car’s performance.

The sound changed, sounding more mean and loud. It gave the exhaust an exotic new look. It has a very pleasing sound that is not disturbing to the hearing.  

Although I did not notice any power gain when testing the new upgrade, this could be due to some factors, which we will look into as we go on. 

Related article: 6 Car Exhaust Parts Explained (With Labeled Diagram)

What is Catback Exhaust?

Cat-back exhaust refers to parts of the exhaust system found at the back of the catalytic converter, including the muffler, rear-pipe, and other cars models; it may include having the x-pipe or Y-pipe.

People are not always satisfied with the performance of their vehicles, especially when it comes to the vehicle’s sound. Hence, they opt for upgrading their exhaust by modifying the cat-back exhaust system.

A cat-back exhaust modification is an upgrade to a  vehicle’s exhaust system to improve its airflow. It is done by replacing the regular stock muffler in the vehicle with a  less restricting one, making airflow better. 

The aftermarket cat-back exhaust system is made in such a way to have more space than the stock exhaust. The exhausts allow the car to have more breathing space, reducing the engine’s constraint.

Catback exhaust refers to the exhaust parts found after the catalytic converter (CAT) and back. This usually includes muffler, exhaust pipes and tips.

Does Cat-back Exhaust Add Horsepower?

Cat-back will add horsepower to your engine because it allows free flow of air from the engine through the exhaust system. A good cat-back exhaust will increase your car’s horsepower by 2 to 5%. 

It is essential to know that the effect of cat-back exhaust horsepower still boils down to the structure of the existing exhaust system and catalytic converter. The existing exhaust system must have enough room for the cat-back system to perform as expected.

Cars generate power to run through what is called combustion, which is delivered through the combustion chambers. The ignition of fuel causes combustion in this chamber, allowing the vehicle to move.

Now, the combustion chamber needs oxygen to perform better, and this is where the exhaust comes to play.

The exhaust allows oxygen into the engine, making the engine perform better, which means the more oxygen in the engine, the more horsepower and performance. Cat-back exhaust allows more oxygen into the combustion chamber, increasing the car’s horsepower.

Most vehicle horsepower losses are mainly related to their exhaust system, limiting the car from reaching its full ability. Vehicles can lose up to 10 to 20% of power owing to a flawed exhaust system.

Does Cat-back Exhaust Enhance Sound? 

The cat-back exhaust system definitely enhances the sound of your vehicle. Make sure you test the sound of the catback before buying – each catback can provide different types of sound. 

Using cat-back has become one of the most popular ways to enhance car sounds; because it is cheaper and allows users to use the catalytic converter.  

In addition, the cat-back exhaust gives users a deeper and more exotic sound, which makes it enjoyable to use. The cat-back has a unique sound that is very pleasing to the ear.

However, you can further enhance the sound of your cat-back exhaust system by changing the muffler. Specific mufflers are designed to give out specific sounds to suit your desire.

To get the desired sound from your cat-back, it is important to specify to the dealer what type of sound you want from your cat-back exhaust. There are many cat-back exhaust systems in the market today, and they have varied sounds they give out.

As a buyer looking to get a better sound from your vehicle, you must know the type of sound you want. 

If you are looking for a better rumble for your exhaust system, you should choose a cat-back exhaust with mandrel bending. The mandrel bending is the secret behind the exhaust, deep rumbling sound that it gives out.  

Another crucial thing to note is constantly checking the local news about the laws guiding the sound emission of vehicles. You do not want to get an exhaust that will get you in trouble with the authorities. 

Cost Of Cat-back Exhaust

The price of a cat-back exhaust system varies depending on many factors. Its exhaust system has a price ranging from $300 to $1200.  The cat-back is one of the best and cheapest ways to improve your car’s performance. 

The varying price of the exhaust system is mainly due to factors like materials used to make the exhaust system and customization to suit the user’s taste.

When it comes to the material used to make the cat-back exhaust, you have to choose between stainless steel or aluminized steel. The stainless steel cat-back exhaust systems are considered more expensive but have better performance and are durable since they do not oxidise and rust over a long period of it being used.

However, aluminized steel is cheaper when compared to stainless steel. Getting aluminum steel is the best way to save money on buying an exhaust system while still having most of the benefits of the cat-back exhaust system.

The Aluminium steel cat-back exhaust system is made from traditional steel coated in the aluminum alloy; this makes the steel resistant to rust. 

Also, designs add to the cost of the cat-back exhaust system. People looking to buy the cat-back exhaust system have to choose an exhaust system with a design that will suit their vehicle. 

They are left to choose between the split rear or the custom cat-back design. They both do not cost the same; their prices are related to their specific designs.

Your car model can also influence the price of the exhaust system. You can be sure that luxurious cars will cost more to upgrade to a cat-back exhaust system. It is the same with big trucks. 

What accounts for most of the price of the cat-back exhaust is the parts. Parts of the general exhaust system depend on what parts you choose to include. Generally, parts should cost between $150 to $1000 but can be much more expensive for some specific brands of vehicles. 

One part of the exhaust system that could add to the cost is the muffler which is not necessary to buy but serves as an excellent way to get the best sound from your exhaust. The muffler and muffler tip could cost from $70 to $300, depending on your desired performance.

Finally, on this aspect, the cost of the cat-back exhaust is the cost of installation. The installation of a cat-back exhaust system is effortless and does not take time. Any mechanic can install the exhaust system within 30 minutes to an hour, and it should not cost much to install.

Do You Need Tuning After Installing Cat-back? 

The cat-back does not need tuning; the exhaust upgrade only covers exhaust parts that can be seen after the catalytic converter.

Hence, new parts of the exhaust system added due to the cat-back upgrade are not affected by sensors that the Engine Control Unit would run on your vehicle. 

Although, it is recommended that you tune your car when changing the complete exhaust system, especially the exhaust headers. Engine Control Unit (ECU) tuning helps correct the air or fuel ratio level in your vehicle. 

If you do not tune your vehicle after installing your cat-back exhaust system, your vehicle will work perfectly because the cat-back exhaust system does not require tuning.

Also, if you decide to tune your car after the upgrade, it will not cause any damage to your vehicle. Only major performance modifications like the exhaust header require tuning.  

Is Cat-back Exhaust Legal?

The cat-back exhaust is entirely legal in all 50 states because the modification does not affect the car’s emission. However, different states in the US have different laws regarding the amount of noise a car can produce. 

For instance, there is a limit of 95 decibels placed on all cars’ exhaust sound in California, meaning that once your car produces a sound of more than 95 decibels, it becomes illegal.

It is nothing to worry about; most cars with Cat-back exhaust systems produce sounds that do not exceed 75 decibels.

You must understand whatever the local law says about car noise emission in your locality. As we know, laws vary in different states in the United States and even beyond the United States.      

Which is Louder Cat-back or Muffler Delete?  

Muffler delete is a bit louder than the cat-back exhaust system. They both give out different sounds, but people prefer the cat-back. The muffler deletes, though louder than cat-back, does not have a preferred sound. 

The muffler delete is completely removing the muffler system from the vehicle. Suppose you do not know what a muffler is. In that case, a muffler has the sole aim of regulating the noise from the engine, thereby making your vehicle sound less noisy, which is done by putting pressure on the exhaust, limiting the airflow, and slowing down your car’s performance.

The process of removing the muffler will increase the performance of the vehicle and also enhance its sound. One disadvantage of the muffler delete is that it is unpredictable.

Having a muffler delete done on your car may have either desirable or non-desirable effects depending on the model of the car you are using. Some cars end up with better sounds while others do not.

On the other hand, the cat-back always gives your car a more excellent and exotic sound. It may not be as loud as the muffler delete, but it is a reliable way to improve your vehicle’s sound. 

If you decide to opt for a muffler delete, you can be sure to expect a sound from your car that may be discomforting to you. 

Related article: Muffler Delete Vs Resonator Delete: Sound, Power & Cost

My Recommendation

Here are some of the cat-back exhaust I will recommend you get and why they stand out: 


1. Flowmaster 817692 cat-exhaust system

The Flowmaster 817692 has built a reputation for itself in the exhaust market. It is a cat-back exhaust made from one of the best stainless steel materials designed to give your vehicle the desired performance you want.

The exhaust is the best for trucks like the Toyota Tundra, producing an aggressive sound that all genuine car lovers will love.

It also comes with a dual emission that can be fixed at the rear or side of the vehicle. The performance of Flowmaster 817692 is a result of the 3-inch bent dual mandrel and 10 mufflers made of stainless steel. 

Installation is made easy for anyone due to the exhaust system’s installation kit.  

Flowmaster 817692 Outlaw Cat-back


2. Dynomax 17340 cat-back system:

The Dynomax 17340 cat-back exhaust system is created to enable your vehicle to achieve its optimum potential. The exhaust system includes a bent mandrel, and it is made of aluminized steel for durability and a better look. It also has one of the best sound quality due to its improved super turbo mufflers. 

Dynomax 17340 Cat-back


3. Magnaflow 16518 cat-back exhaust system:

The Magnaflow 16518 is another well-known exhaust in the market today that offers your vehicle more power than other exhaust systems you can find around. It is known for its durability and extra horsepower through the added punch to the engine.

It is made from stainless steel and features a 4-inch single slash tip and a 3-inch mandrel benty tailpipe. This feature is what gives extra horsepower to your vehicle. 

The exhaust system will give you years of high performance, and I also suitable for any type of vehicle, ranging from SUVs, trucks, or race cars. It is also suitable for all vehicles regardless of how long they have been used.  

MagnaFlow Exhaust 16518

Ifandi L.

Ifandi L.

Passionate about everything mechanical. Ifandi has been involved with motorcycles and cars since the old days - in his family's auto parts shop. Want to keep in touch? Scream "STRAIGHT PIPEEEEE" at the top of your lungs and Ifandi will show up.

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