Header first or exhaust first? That’s a tough question. Both improve exhaust flow and can gain you extra horsepower and sound. So which one? The answer is….. It depends on you – let me explain!
For the busy people – You should go for headers first if you care mostly about performance and the number of horsepower. Go for an exhaust system first if you want a much improved sound and don’t mind the minimal horsepower gain.
For the less busy people, stick around. I will compare headers and exhaust in details – covering various aspects like performance, sound, price, installation and warranty.
After reading this article, you should know which of the two to pick. But for now, let’s get the basics right first.
Recap: What’s The Use Of Exhaust Headers?
Exhaust headers collect exhaust gases that are leaving the combustion chamber and merge them into a single flow. Exhaust headers are thin, made of stainless steel and have even lengths – allowing exhaust gases to flow efficiently.
Let me explain why thin and even length headers are important.
In case you don’t already know, a car engine generates combustion to move. Combustion is an explosion that requires air and fuel. The more air available in the combustion chamber, the more power is generated.
Which is why it’s important to quickly free up the combustion chamber of all exhaust gases that are produced along with the combustion. The faster this is done, the more room is available for air to enter and create bigger combustion.
Factory cars usually come equipped with exhaust manifolds. They are responsible for the same thing as headers – merge exhaust gases coming from the combustion chamber into a single flow.
Except, exhaust manifolds are made of cast iron (much thicker) and have uneven lengths. Uneven lengths mean that exhaust gases will likely collide when they meet at the merging point. This creates additional pressure that will slow down the movement of exhaust.
Which is why exhaust headers are used. Their thinness allows more room for exhaust gases to travel and their even lengths make sure exhaust gases arrive at the merging point consistently – no more collision, no more extra pressure.
This greatly improves exhaust flow in your car. Now your car’s combustion chamber has more room for air to enter and create bigger combustion – resulting in extra horsepower.
See the difference between a header and a manifold below. It should clear things up. Click on the places I have marked for more explanation.
Recap: What’s The Use Of Exhaust System?
A car exhaust system is responsible for transporting exhaust gases to outside the car. An exhaust system is equipped with various components like catalytic converter (CAT) and muffler. A CAT converts toxic gases into their non-toxic version, whereas a muffler silences the sound waves that are also travelling in the exhaust.
Similar to an exhaust header, exhaust systems can be replaced with their performance versions – which have wider diameter. Thus, reducing pressure and allowing exhaust gases to travel and leave quickly.
When exhaust gases leave quickly, it means more room for air to enter the combustion chamber. This allows for bigger combustion and thus, extra horsepower.
Performance aside, performance exhausts also come with performance mufflers – which are designed to make louder and aggressive noise.
So does this mean performance exhaust gives you extra horsepower and louder sound? Yes sir!
Before we move on to the comparison between header and exhaust, I want to talk a bit on the different types of exhaust systems. There are 3 of them:
- Header-back exhaust replaces everything from the header back. This includes catalytic converter (CAT), mufflers and all exhaust piping till the tail. This is the most expensive type and will yield you most horsepower and sound improvement.
- Cat-back exhaust replaces everything from the catalytic converter (cat) back. This includes mufflers and all exhaust piping till the tail. This is the most popular – it will yield you some horsepower and sound.
- Axle-back exhaust replaces everything from the axle back. This includes mufflers and a small amount of piping till the tail. This is the cheapest option.
In this article, I will only compare catback exhaust with the header. Catback exhaust is the most popular choice among enthusiasts. They provide the best bang for your buck – some horsepower improvement and great sound.
Headers Vs Exhaust
Here’s a comparison table. More detailed explanation below.
|Horsepower||15-20 horsepower||5-10 horsepower|
|Sound||Minor improvement||Major improvement|
|Tune Required||Yes (Recommended)||No|
|Visible Outside||No||Yes (Tail pipe)|
|Check Engine Light||Yes||No|
Exhaust header at around $700 is cheaper than a catback exhaust at around $1,0000 – mainly because a catback exhaust includes more components like piping, muffler, tailpipe and clamps.
The price will differ depending on your car and the brand. More reputable brands will obviously be more expensive but they are not always the best! You need to do plenty of research on forums, articles and YouTube videos to find the best.
For example, when looking for an exhaust, you need to pay attention to the piping diameter, sound, material and warranty. Here’s an article where I talk about this in depth. Best Aftermarket Exhaust: Which To Buy And What To Look For?
Aftermarket header can provide more horsepower (15-20 horsepower) than a catback exhaust (5-10 horsepower) – especially when tuned. This is because stock headers (manifolds) are usually much more restrictive and they are closer to the combustion chamber.
If you care only for horsepower, then headers are hands-down the better choice than a catback exhaust.
Headers will not provide much sound improvement – although you will have a slightly louder engine sound. This happens because aftermarket headers that are made from stainless steel are thinner – allowing sound vibrations to escape outside.
I cover more about exhaust headers and sound improvement in this article. Do Headers Make Your Car Sound Louder?
Catback exhaust on the other hand will definitely provide sound improvement – loudness depends on the type you buy. This is because catback exhausts come with aftermarket mufflers as well – the component responsible for your car sound.
The good thing about exhaust is that you are free to choose how your car sounds. Just make sure you research the sound on forums and YouTube videos before purchasing. Some exhausts are extremely loud while others are aggressive – yet tolerable.
Personally I go for the Flowmaster Force II Exhaust. They are aggressive but not deafening to the passengers. Check out the article I linked above for choosing exhaust.
Headers are more tricky to install than a catback exhaust. This is because there’s not much room to play around with and you need to be patient in getting the headers in and out.
Catback exhausts are less tricky to install than a header but they require you to loosen lots of nutes and potentially cut off some parts from your stock exhaust.
Both installations can be done at home – there are plenty of tutorials on YouTube. But if you prefer to pay for installation, then I would say header installation costs around $500-$700, whereas a catback exhaust installation costs about $100 – $200.
5. Warranty Voided
If you are living in the US, you should be protected by the Magnuson Moss Warranty act. You could look it up online for details but in short, it prevents dealers from taking away your whole warranty just because you have installed aftermarket parts.
To void your warranty, your dealer must prove how your aftermarket install is a direct cause of your issue.
With this in place, you will still lose parts of your warranty. In general, you will lose warranty for parts that are involved during the install. For example, you will not lose the warranty for your battery after installing a catback exhaust.
6. Tune Required
Both headers and catback exhausts do not require tune to operate – they will still provide you with some horsepower but it could be limited.
Generally, you want to bring your car to a tune after installing headers – you could gain even more horsepower and ensure check engine light is not turned on.
Headers require a tune because they provide a large enough impact on your exhaust flow that your car’s computer (ECU) can’t adjust to.
For catback exhaust, I wouldn’t suggest tuning right away – it won’t increase your horsepower by much. Maybe get the tune only after you have installed other components like performance air filters and cold air intake.
Note that once you tune your car, you could lose warranty on many parts of your car. Tuning involves tweaking the car’s computer – who is responsible for managing how your car components work. I discuss more about tuning here. How Much HP Gain From Dyno Tune?
7. Visible Outside
If you care about the looks, then you might want to go for a catback exhaust instead. Exhaust headers live inside the engine bay and they are not visible from the outside.
Whereas catback exhausts are visible from the outside due to the aftermarket tailpipe that it includes. You could even get a resonator exhaust tip if you want your car to look aggressive and sound even louder.
8. Check Engine Light
Installing headers will most likely cause your Check Engine Light (CEL) to turn on. Again, this is because the exhaust flow changes by an exhaust header is significant enough to throw a CEL.
You can get this CEL to turn off by tuning your car.
On the other hand, catback exhaust will not change your exhaust flow to the point where CEL is on. So you don’t have to worry about that.
Now that we have compared headers and catback exhaust in detail, let’s summarize by choosing which aftermarket part you should go for based on your goal.
Headers Or Exhaust First: For Performance
For performance and horsepower gain, you definitely should go for headers. They provide more horsepower (15-20 horsepower) and even more if you decide to bring your car for a tune.
Exhaust headers significantly reduce the restriction on your car’s exhaust flow – causing them to flow out faster and allowing more oxygen to enter the combustion chamber to generate more power.
Headers Or Exhaust First: For Sound
For an improved sound. You should install a catback exhaust instead of headers. Catback exhausts or any exhausts really, come pre-installed with a performance muffler that will make your car sound louder and more aggressive.
Before choosing the exhaust, you could listen to the before and after sound from YouTube videos or forums. This way, you can get the exact sound improvement that you want.
Headers Or Exhaust First: My Take
Personally, I would go for exhaust first. Overall they are just a little more expensive than headers (considering installation fee) – but in exchange they provide you with a great sound, looks and some horsepower.
For horsepower, I would look for other components to replace – something that will give me even more of a boost. At the top of my mind, I am thinking of downpipe or even installing a turbo!
Here’s my article about downpipe if you want to know more about it. Are Downpipes Worth It?