Does A Cat-Back Exhaust Increase Horsepower? (The Truth)

Installing a cat-back exhaust is one of the easier modifications that you can make to your car, for a relatively inexpensive price. A lot has already been said about how cat-back exhausts can change the sound of your car, which has led many to wonder whether they can also increase horsepower.

Cat-back exhausts can increase the horsepower of your car, potentially adding up to 12 horsepower, depending on the make and model of your vehicle and the condition that the stock exhaust is in. Cat-back exhausts increase air flow through the exhaust, putting less strain on the engine.

As well as increasing the horsepower of your car, cat-back exhausts can also make your car faster and lead to better fuel economy, as aftermarket exhaust systems are often lighter than stock exhausts. In this article, we will delve deeper into the benefits of cat-back exhausts.

How Much Horsepower Will A Cat-Back Exhaust System Add?

Installing a cat-back exhaust system onto your vehicle can typically add between 2 and 12 horsepower, although this depends on a variety of factors. If you already have a free-flowing exhaust system, then you may not experience much of an upgrade. However, if you have a restrictive exhaust system that prevents the free flow of air, then the level of horsepower added may be more noticeable.

Ultimately, a cat-back exhaust system is only as good as the parts surrounding it. The cat-back system refers to any part of the exhaust that is behind the catalytic converter, which means it will still rely on the rest of the exhaust system to be performing well in order to make improvements. For example, if you have a faulty catalytic converter, a cat-back system will show limited improvements.

If the rest of your exhaust system is in good shape and there is adequate space to fit in a new cat-back exhaust system, then you should be able to feel a real boost in your car’s horsepower. Not everyone will see an increase of 12 HP, as the make and model of your car will have a bearing on the outcome. Nonetheless, cat-back exhaust systems are a good option if you want some extra power.

How Does A Cat-Back Exhaust Increase Horsepower?

A lot of the increase in horsepower brought on by cat-back exhaust systems stems from the fact that stock exhaust systems aren’t manufactured with horsepower as a priority. Stock exhaust systems are designed to use the least number of materials while maximizing space. Aftermarket cat-back systems are usually designed for performance, with wider ends and a reduction of back pressure. 

Aftermarket cat-back exhausts have mandrel bends along with their wider ends, which help to increase the efficient flow of waste gases from the engine. Mandrel bends maintain the same inner diameter all the way through the pipe, unlike many bends used in stock exhausts. This keeps the air flowing at the same velocity throughout, reducing backpressure and increasing overall engine performance.

The most effective component in a car for achieving high horsepower is the turbocharger, and this can also be made more efficient with a cat-back exhaust system. Once again, this comes down to the reduction of back pressure created by having a cat-back exhaust system installed. The reduction in back pressure prevents decreases in the speed of the turbocharger shaft, keeping power levels up.  

Having a cat-back exhaust system will mean that your vehicle won’t have to work as hard as it would with a stock exhaust, due to improved air flow, leaving your engine able to produce its best results. 

Will A Cat-Back Exhaust Make Your Car Faster?

A cat-back exhaust can make your car faster, as not only will you have increased the car’s overall power, but you will have also shaved off some weight by removing a heavier stock exhaust. However, speed gains are usually minimal, and sometimes it won’t be noticeable.

Depending on the system you choose, cat-back exhausts can reduce your car’s weight by around 40 lbs (18 kg). This can make your car feel slightly faster, whether it be around corners or in straight lines.

The additional power that cat-back exhaust systems offer will truly come to fruition when driving on long, straight roads where you can really let loose on the accelerator pedal. A lot of the increased speed does depend on the model of your car, as well as the effectiveness of the stock exhaust system. If the car already had a good exhaust installed, you may not notice as much of a difference.

You will most likely be able to achieve a speed increase between 2-5% of your original top speed when you have a cat-back exhaust system installed. A better flow of gases through the exhaust will result in less strain on the engine, an increase in power, and therefore an increase in overall speed. 


• Cat back exhausts can increase your car’s horsepower

• How much extra HP you get will depend on a variety of factors

• It can make your car slightly faster as a result

The 4 Benefits Of Cat-Back Exhausts

1. Increase In Power

Stock exhausts aren’t built with maximum power in mind but are instead built with the intention of minimizing materials and reducing the overall cost of manufacturing the car. Aftermarket cat-back exhausts are different and are instead made with performance as a priority. Better quality materials and the use of mandrel bends will ensure a better flow of air through the pipes, increasing power.

2. Sound Improvement

If you want your car to sound more aggressive and less raspy, then cat-back exhausts may be the way to go. While they may not always guarantee the car to be substantially louder than before, the tone produced will be richer and deeper, with a lot more bite than stock exhausts are able to produce. 

3. Easy To Install

Cat-back exhausts rarely require any extra modification to install, as they will bolt directly on to where the stock exhaust system once was. They will also come with all the pieces that you need for a full installation, including exhaust pipes, a muffler and exhaust tips. 

Unlike many modifications, cat-back exhaust systems can be installed in a home garage, providing you have the right tools and know what you’re doing.

4. Better Fuel Economy

Installing an aftermarket cat-back exhaust can have a real positive effect on your vehicle’s fuel economy too. For a start, there is less strain on the engine as backpressure in the exhaust system will be reduced. However, the key factor lies in the car’s overall weight

Aftermarket exhausts will usually be made from lighter materials than stock exhausts, therefore reducing the overall weight of your car. Having a lighter car means that the engine won’t have to use as much energy as it would if the car was heavier, meaning your fuel will last longer. Heavy cars also have a lot more rolling resistance, which contributes to higher fuel consumption.

How Much Do Cat-Back Exhausts Cost?

Cat-back exhausts are relatively inexpensive compared to many other vehicle modifications, starting from around $300, excluding labor costs. The cost will vary depending on the materials, the size and model of your car, and whether you want to buy the exhaust as a full set or in individual parts. 

Prices can rise to around $1500, especially if you are replacing the exhaust on a luxury car or an exceptionally large vehicle. This is because these exhausts require more materials to manufacture, as well as often requiring more components than you would need if you were replacing the exhaust on a smaller car. The quality of materials used will also affect the price of the exhaust system.

Cheaper steel components will cost the least, with stainless steel components costing the most. Most mid-range parts will be made from aluminum. You should take into consideration where you live before making the decision on which materials to go for. If you drive through a lot of country roads, you will likely require the strongest materials as they will be more exposed to wear.

Labor costs also need to be considered, unless you plan on replacing the exhaust yourself. If you have a home garage with basic modification tools to hand, you may be able to sidestep any labor costs by doing the job yourself. However, the easiest option would be to pay a professional to do the work for you. The cost of this will vary depending on the garage that you choose for the replacement.

Will A Cat-Back Exhaust Void Your Warranty?

A cat-back exhaust will not void your warranty unless something is damaged as a direct result of having the cat-back exhaust system installed. This is why it’s key to have proof of the cause of any damage that does occur not as a result of the exhaust system.

It is often believed that when you buy a product, whether it be a car or anything else covered by a warranty, that you must solely use it with the original parts that it came with, otherwise you risk losing your coverage. In the US, goods protected by a warranty are covered by the Magnuson Moss Warranty Act, aimed to protect customers from unfairly losing their warranty on a range of goods.

While the act isn’t specifically car oriented, it is still a valid means of protection, especially if you are being denied your warranty because of the installation of aftermarket parts. The act forbids manufacturers from forcing their customers to use only original parts (stock parts in this case), or specific name brand products. 

What Caused The Damage?

However, the act doesn’t mean that you can get away with changing the entirety of the car’s parts. If damage is done as a result of installing an exhaust system, or the exhaust is defective in any way, then you may be denied coverage by the manufacturer or dealer that you purchased the car from. It’s important to have proof that damage had nothing to do with an aftermarket exhaust being installed.

Manufacturers are also not permitted to deny you your warranty if you have had the exhaust installation done by a third-party garage, or even by yourself. In short, you can only have your warranty denied if the aftermarket cat-back exhaust has caused the damage that needs repairing. You cannot lose your warranty simply by having an aftermarket exhaust system installed. 

Will A Cat-Back Exhaust Make Your Car Louder?

Cat-back exhausts can make your car sound louder and more aggressive. This is because of both the pipes used and the larger diameter of the tail pipes. A lot of cat-back exhaust systems come with mufflers that have less sound-absorbent materials in them, allowing for the richer, deeper sounds. 

The mandrel pipes that are so commonly used in cat-back exhausts help to produce a throaty, rumbling sound, which is accentuated because of the greater air flow that they allow. The consistency of the inner diameter of mandrel pipes means that sound waves won’t have to alter their course dramatically, like they would with crush-bend pipes. 

The larger diameter of cat-back exhaust pipes act as an amplification device for the sound waves as they exit the vehicle. Whereas narrower tail pipes are more restrictive with sound, wide pipes allow it to have more freedom of movement. Sound will be further altered depending on the type of exhaust tips that are fitted to the exhaust system.

Is A Cat-Back Exhaust Worth It?

The benefits that cat-back exhausts offer may make them worth the money you will have to pay. In the long-term they can save you money by improving your car’s fuel efficiency. They can also slow down engine degradation, as they help to reduce backpressure and strain on the engine’s mechanics. 

Aside from the long-term financial benefits, cat-back exhaust systems can improve your car’s performance. Cat-back exhausts can increase your car’s horsepower as well as its top speed. In addition to this, your car will sound more aggressive than ever, producing deep, rich tones. 

The positive effects of having a cat-back exhaust installed will be obvious from the start, and the fact that having one installed won’t affect your warranty makes them a relatively risk-free modification too.


• Cat-back exhausts can have many benefits for your car

• They can increase your top speed and change the sound of your car too

• They’re usually not too expensive to install, and they won’t void your warranty

Final Thoughts

Cat-back exhausts can increase your car’s horsepower by about 12 HP. This can increase your car’s top speed and improve your overall driving experience. Installing a cat-back exhaust is a simple and inexpensive process that will offer you noticeable changes in the way your car runs and operates.

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