Unlocking your vehicle’s potential starts with a deep understanding of the components of its exhaust system. This network of intricate pipes and components doesn’t just work together to eliminate gases from the engine—it’s key to achieving fuel efficiency and raw power.
When it comes to optimizing your vehicle’s exhaust system, understanding the difference between exhaust manifolds and headers is crucial. In this article, we’ll explore the key differences, benefits, and ideal applications of these two exhaust parts, to help you make informed decisions for your vehicle.
What’s the Difference Between Headers and Exhaust Manifolds?
Headers and exhaust manifolds are both essential components of a vehicle’s exhaust system, each designed with specific functions and benefits tailored to different vehicle needs. Here’s a breakdown of their key differences:
Material and Construction
Headers typically consist of separate tubes that merge into a collector. Every tube is the same length on a properly built set of headers, thus the elaborate bending. They are usually made of thin yet highly durable stainless steel (but they can also be made of other materials such as ceramic-coated steel).
Meanwhile, exhaust manifolds are generally made of cast iron or steel and feature a compact design due to manufacturing budgets and space limitations in the engine bay. Headers are lighter and more efficient than heavy cast iron exhaust manifolds, and they actually run cooler because the piping is thinner and doesn’t absorb and retain heat like a manifold.
Performance
Headers enhance vehicle performance by increasing exhaust flow, allowing the engine to breathe more freely. This increased flow can potentially boost horsepower and torque, making them more suitable for racing and high-performance applications.
Exhaust manifolds, on the other hand, are better suited for daily driving and produce less exhaust noise than headers. However, noise levels are also influenced by the muffler, so a vehicle with headers can still be as quiet as one with a manifold.
Notably, many newer vehicles come with headers by default, even if they’re not high-performance models. For instance, Jeep Cherokees with 4.0L engines from the late ‘90s and many 4-cylinder engines are equipped with headers, often using the light-off catalyst as the collector.
Heat Regulation
Exhaust manifolds can become extremely hot, transferring heat to nearby engine components and potentially affecting their durability.
Headers, in contrast, often come with heat shields or coatings to manage the high temperatures generated by exhaust gases. Since headers radiate more heat than standard manifolds, ceramic coatings or heat wraps are especially important in high-performance applications to effectively manage heat and protect surrounding components.
Cost
Due to their materials and advanced design, headers are considered an expensive upgrade. Some can even be custom-designed for specific vehicles.
Exhaust manifolds are generally more affordable as they are simply original stock parts on most vehicles.
Installation
Headers can require more complex and careful installation, and additional modifications may also be needed to fully utilize their benefits. Meanwhile, exhaust manifolds are installed by the factory, and compatible replacements can be easily installed without any complex modifications.
Fuel Consumption
By reducing back pressure in the exhaust system, headers allow for better exhaust flow, which means that the engine can expel exhaust gases more efficiently, which can lead to minor improvements in fuel consumption.
What is an Exhaust Manifold?
The exhaust manifold is a standard component pre-installed on most production vehicles. It serves as the initial part of the exhaust system. It is tasked with collecting exhaust gases from the engine’s cylinders and funneling them into a single outlet leading to the light-off converter that handles NOx and then to the secondary converter that handles CO and HC. The latter then reduces harmful emissions before the gases continue through the exhaust tailpipe and muffler, where noise is reduced, before being expelled from the vehicle.
What Does an Exhaust Manifold Do For Your Car?
An exhaust manifold’s primary purpose is to manage the flow of exhaust gases from the vehicle. By efficiently directing hot gases away from the engine, the manifold helps reduce backpressure. In addition, the process also effectively removes any pollutants and optimizes the entire exhaust system, leading to enhanced engine performance and functionality.
Where is the Exhaust Manifold Located?
The stock exhaust manifold of your vehicle is typically found on the side or top of the engine, positioned between the cylinder head and the catalytic converter. Depending on the vehicle design and engine type, there may be more than one exhaust manifold—especially in V-type engines, where a manifold is securely bolted to each cylinder head.
What is a Header?
Headers are aftermarket upgrade parts used to replace a vehicle’s stock exhaust manifolds, primarily to add more power for high-performance applications. They perform the same function as manifolds, except that they create less exhaust backpressure for more efficient engine breathing.
What Do Headers Do?
As mentioned, the main purpose of an exhaust header is to reduce backpressure in the exhaust system, effectively extracting exhaust gases instead of forcing the engine to overcome the flow from adjacent cylinders during each cycle. By having multiple exhaust pipes leading to a collector, the header allows exhaust gases from each cylinder to exit more efficiently with minimized airflow resistance, thereby improving the engine’s ability to “breathe.”
What Do Headers Do For a Car’s Sound?
Aside from enhancing the overall performance of your vehicle, installing a header is a modification that’s hard to miss, as it will also produce a noticeable change in exhaust tone. When you upgrade to a header, you get a smoother, more aggressive, and well-defined sound when you rev your engine.
Of course, the mufflers you choose will also affect the sound of the exhaust.
Exhaust Manifolds vs Headers: Which is Right For You?
It depends on what you’re looking for. Performance and efficiency? Go for a header. Simplicity and cost-effectiveness? Stick with the exhaust manifold.
For daily driving that involves navigating traffic and cruising on highways, the disadvantages of headers often outweigh the benefits. You may want to focus on keeping up with regular maintenance, as well as investing in good tires and other modifications that can boost everyday drivability without sacrificing vehicle comfort and reliability.
However, if your weekends are dedicated to joyrides, occasional speed racing, and showcasing your car, headers could be a valuable and rewarding upgrade.
Frequently Asked Questions
How much horsepower do exhaust headers add?
Headers generally boost horsepower by 5 to 20 HP, depending on the specific engine, exhaust configuration of your vehicle, and even the quality and design of the headers themselves. High-performance headers from well-known manufacturers such as Flowtech and Kooks, are typically at the higher end of the horsepower range.
Are headers worth it?
Yes, as long as you choose a header that suits your vehicle and driving style. If you’re willing to invest the time and money to make them work for your car, headers can be a very worthwhile upgrade.
