Knowledge about exhaust systems is usually limited to pipes, converters, and mufflers. Most people think that the exhaust system only takes exhaust fumes from the engine and makes a specific engine sound, however, it’s a more complex system.
One of the most important components of an exhaust system is the exhaust manifold. In this article, we’ll talk about exhaust manifolds, but also the aftermarket components used to replace manifolds for better performance – headers. Although their goal is basically the same, there are a few distinct differences between them, and we’ll also cover those.
What Are Headers?
Exhaust headers are commonly referred to as aftermarket performance components that replace exhaust manifolds to increase power by eliminating exhaust flow restrictions. Although most production cars are factory-fitted with manifolds, some high-performance cars are fitted with headers, too.
There are four main types of headers available on the market, which include long-tube headers, shorty headers, Lakester headers, and lastly tri-Y headers. Each type of header is made for a specific application.
Long-tube and shorty headers are most commonly used in passenger cars. Long-tube headers are the best choice when an improvement in low and mid-range torque is required, while shorty headers provide more power at a higher RPM range. Shorty headers are also less noisy than long-tube headers. Aside from more power, headers provide better exhaust flow and better sound.
To get the best performance from headers, it’s recommended to replace the entire exhaust system for the best effect. Aside from this, there are a few other things you need to do to fit a header and make it work properly. Most modern cars use a number of computers and sensors to adjust parameters for the best performance, and less fuel consumption and emissions. Just swapping a manifold for a header will significantly alter the factory-set parameters, and you’ll need to edit ECU parameters to make the car perform as well as it should.
What Are Exhaust Manifolds?
Exhaust manifolds are stock exhaust system components found in most production cars. They’re usually made from cast iron or stainless steel, and their primary function is to collect exhaust gasses from the engine and deliver them to the catalytic converter.
Due to the design, and materials used for production, exhaust manifolds reduce emissions, heat, and make less noise than exhaust headers. The design of exhaust manifolds restricts exhaust flow in order to comply with automotive emissions regulations, at the cost of performance. This is why replacing exhaust manifolds with headers are amongst the more popular performance modifications on the exhaust.
Difference Between Headers and Manifolds
To many, exhaust manifolds and headers are the same. Although they serve the same purpose, they’re different exhaust system components that affect a car’s performance. The common thing these components share is their function which is to collect exhaust fumes and deliver them to the end of the exhaust system. The difference between them is the materials they’re made of, and the design. This significantly affects the car’s performance.
Exhaust manifolds are most commonly stock exhaust system parts made from cast iron which is thick and leaves little space for the exhaust fumes to pass through. Headers on the other hand are made from stainless steel which is thinner and provides better exhaust flow compared to manifolds. The thinner tubes don’t absorb as much sound as manifolds do, so aside from better performance, you can expect louder exhaust sounds, too.
The main design difference between headers and manifolds is that headers have longer tubes that feed exhaust gasses to a collector. This simple, yet effective design change eliminates back pressure because fumes aren’t pushed into a pipe so close to the engine. Even if headers were made from cast iron, a significant performance increase would be felt.
Which is Better?
By now, it’s clear that headers and exhaust manifolds have the same function, but are done differently. As we’ve mentioned, headers and manifolds are designed differently and each of the components has its pros and cons.
Stock manifolds are factory-fitted to adhere to the strictest automotive regulations, however, these same manifolds restrict the engine from breathing freely and providing power to the wheels. Headers are considered performance upgrades due to their design and material, and their ability to reduce the backpressure when delivering exhaust fumes to the exhaust tip.
Saying which is better is difficult because it depends on what you want from your car. If you want to comply with automotive standards and environmental regulations, it’s better to keep the stock manifold fitted to your car. On the other hand, if you’re interested in performance and sound, headers are the choice to go with. You’ll also need to consider whether you need increased performance at lower revs, or higher because not all headers are made the same.
One of the main things to consider is that headers won’t provide a significant power increase if other aspects of the engine are kept stock. Fitting a header on a stock car is a simple bolt-off bolt-on process, however, headers can lead to damage to other components in the engine compartment. This is why it’s not recommended to use performance headers in daily drivers.
Are Headers A Worthwhile Upgrade?
Exhaust headers aren’t parts that easily break out of the blue, and when they’re replaced, it’s usually for a certain performance gain, and less often due to manifold failure.
When it comes to the price, headers are higher in the price range than replacement exhaust manifolds and taking into consideration all the performance benefits that are related to headers, many still ask whether headers are something they should invest in. A performance exhaust header that’s legal, and provides noticeable improvement costs more than $500, but the power gain can be up to 20 horsepower. If you add other modifications that need to be done to the car so the header would be as effective as possible, you can be looking at upgrades easily worth more than $1000.
Depending on what you’ve already done to your car, you can invest this in other performance upgrades that will add more power or performance capabilities to your car compared to headers.