Aftermarket Headers: Improving Exhaust Flow and Horsepower

Aftermarket headers can significantly improve exhaust flow and increase horsepower This guide covers different header designs and materials helping you choose the best option for your engine Unleash your engine's hidden power with improved exhaust flow

Understanding Aftermarket Headers and Exhaust Flow

So, you're thinking about upgrading your exhaust headers? Awesome! It’s a fantastic way to squeeze more power out of your engine. But what exactly are headers, and why are they so important for exhaust flow? Let's break it down.

Your engine creates exhaust gases as a byproduct of combustion. These gases need to be efficiently expelled from the cylinders to make room for the next combustion cycle. Stock exhaust manifolds are often restrictive, designed for cost-effectiveness and noise reduction rather than optimal performance. Aftermarket headers, on the other hand, are engineered to provide a smoother, less restrictive path for exhaust gases to escape.

Think of it like this: imagine trying to pour water through a narrow straw versus a wide pipe. The wider pipe allows for a much faster and smoother flow. Headers do the same thing for your engine’s exhaust.

Better exhaust flow translates to increased horsepower and torque. When the engine doesn't have to work as hard to expel exhaust gases, it can breathe easier and produce more power. Plus, a good set of headers can give your car a throatier, more aggressive sound – a definite bonus for many enthusiasts!

Header Designs Long Tube vs Shorty Headers Explained

Now, let's dive into the different types of header designs. The two main categories are long tube headers and shorty headers (also known as short tube headers or mid-length headers). Each design has its own advantages and disadvantages, so it's essential to choose the right one for your specific needs and goals.

Long Tube Headers

Long tube headers, as the name suggests, feature longer primary tubes that extend further down the engine bay. These longer tubes are typically tuned to optimize exhaust flow and create a scavenging effect, which helps to pull exhaust gases out of the cylinders more efficiently.

Pros:

• Maximum Performance Gains: Long tube headers generally provide the biggest horsepower and torque gains, especially in the mid-range and top-end of the RPM band.
• Improved Scavenging: The longer tubes and tuned design create a scavenging effect that enhances exhaust extraction.

Cons:

• Installation Complexity: Long tube headers can be more challenging to install, often requiring modifications to the exhaust system and potentially even the chassis.
• Ground Clearance Issues: The longer tubes can sometimes reduce ground clearance, making them more susceptible to damage on lowered vehicles or rough roads.
• Emissions Compliance: Long tube headers often eliminate catalytic converters, which may make them illegal for street use in some states. Always check local regulations!

Shorty Headers

Shorty headers are a more compact design with shorter primary tubes. They are generally easier to install than long tube headers and often retain the factory catalytic converters.

Pros:

• Easier Installation: Shorty headers are typically a direct bolt-on replacement for the factory exhaust manifolds, making installation much simpler.
• Emissions Compliance: They usually retain the factory catalytic converters, making them street legal in most areas.
• Better Ground Clearance: The shorter design provides better ground clearance compared to long tube headers.

Cons:

• Smaller Performance Gains: Shorty headers generally provide smaller horsepower and torque gains compared to long tube headers.
• Less Efficient Scavenging: The shorter tubes are less effective at scavenging exhaust gases.

Header Materials Stainless Steel vs Ceramic Coated Headers

The material your headers are made from significantly impacts their durability, performance, and price. The two most common materials are stainless steel and ceramic-coated steel.

Stainless Steel Headers

Stainless steel headers are known for their durability and resistance to corrosion. They are a popular choice for both street and track applications.

Pros:

• Excellent Durability: Stainless steel is highly resistant to rust and corrosion, making it a long-lasting option.
• Good Heat Resistance: Stainless steel can withstand high temperatures without warping or cracking.
• Aesthetically Pleasing: Stainless steel has a clean, polished look that can enhance the appearance of your engine bay.

Cons:

• Higher Cost: Stainless steel headers are generally more expensive than ceramic-coated steel headers.
• Heat Dissipation: Stainless steel doesn't dissipate heat as efficiently as ceramic coatings, which can lead to higher engine bay temperatures.

Ceramic Coated Headers

Ceramic-coated headers are typically made from mild steel and then coated with a ceramic coating. This coating provides excellent heat insulation, which can help to reduce engine bay temperatures and improve performance.

Pros:

• Excellent Heat Insulation: The ceramic coating significantly reduces heat transfer, keeping the engine bay cooler.
• Improved Performance: Reduced heat soak can improve engine performance and prevent heat-related issues.
• Lower Cost: Ceramic-coated headers are generally less expensive than stainless steel headers.

Cons:

• Less Durable: The underlying mild steel is more susceptible to rust and corrosion compared to stainless steel.
• Coating Damage: The ceramic coating can be damaged by impacts or improper handling.

Choosing the Right Header Diameter and Collector Size for Your Engine

Selecting the correct header diameter and collector size is crucial for optimizing exhaust flow and maximizing performance gains. The ideal size depends on your engine's displacement, horsepower goals, and intended use.

Header Diameter:

The header diameter refers to the size of the primary tubes. Smaller diameter tubes are generally better for low-end torque, while larger diameter tubes are better for high-end horsepower.

Collector Size:

The collector is the point where the primary tubes merge together. The collector size also affects exhaust flow and performance. A collector that's too small can restrict exhaust flow, while a collector that's too large can disrupt the flow and reduce performance.

As a general rule of thumb:

• Smaller Engines (under 2.0L): 1.5" - 1.75" primary tubes, 2.25" - 2.5" collector
• Mid-Size Engines (2.0L - 3.5L): 1.75" - 2.0" primary tubes, 2.5" - 3.0" collector
• Larger Engines (over 3.5L): 2.0" - 2.25" primary tubes, 3.0" - 3.5" collector

It's always a good idea to consult with a performance specialist or exhaust expert to determine the optimal header diameter and collector size for your specific engine and application.

Recommended Aftermarket Header Brands and Products with Pricing

Okay, let's get to the good stuff! Here are a few recommended aftermarket header brands and specific product examples, complete with estimated pricing and use cases. Prices can vary depending on the vendor and any ongoing sales.

1. BBK Performance Headers

BBK is a well-known brand offering a wide range of headers for various applications, particularly popular with Ford Mustang and GM enthusiasts.

Product Example: BBK Long Tube Headers for 2011-2014 Ford Mustang GT 5.0L

• Use Case: Ideal for Mustang owners looking for significant horsepower gains and an aggressive exhaust note. Best suited for modified engines.
• Features: 1-3/4" primary tubes, 3" collector, mandrel-bent tubing, available in chrome or ceramic coating.
• Estimated Price: $600 - $900

2. Edelbrock Headers

Edelbrock is a trusted name in performance parts, offering high-quality headers for a variety of vehicles.

Product Example: Edelbrock TES Headers for Small Block Chevy

• Use Case: Excellent choice for classic Chevy owners seeking improved exhaust flow and moderate performance gains.
• Features: Shorty design, 1-5/8" primary tubes, 2.5" collector, coated for corrosion resistance. Emissions legal in many states.
• Estimated Price: $400 - $600

3. Flowmaster Headers

Flowmaster is famous for their mufflers, but they also produce excellent headers, often designed to complement their exhaust systems.

Product Example: Flowmaster Scavenger Series Long Tube Headers for Dodge Challenger/Charger 5.7L Hemi

• Use Case: Perfect for modern Hemi owners wanting maximum performance and a signature Flowmaster sound.
• Features: 1-7/8" primary tubes, 3" collector, stainless steel construction, mandrel-bent tubing.
• Estimated Price: $800 - $1200

4. PLM (Private Label Mfg) Headers

PLM is known for their high-quality, affordable performance parts, particularly for import vehicles like Hondas and Nissans.

Product Example: PLM Tri-Y Header for Honda Civic/Integra B-Series

• Use Case: A great choice for Honda enthusiasts looking to improve mid-range power and throttle response.
• Features: Tri-Y design, stainless steel construction, mandrel-bent tubing, optimized for B-series engines.
• Estimated Price: $300 - $500

5. Kooks Headers and Exhausts

Kooks is a premium brand specializing in high-performance headers and exhaust systems for a wide range of vehicles. They are known for their exceptional quality and performance gains.

Product Example: Kooks Long Tube Headers for Chevrolet Camaro SS 6.2L

• Use Case: Ideal for Camaro SS owners who want the ultimate in performance and sound. These headers are designed for maximum power gains and are often used in racing applications.
• Features: 1 7/8" or 2" primary tubes (depending on your power goals), 3" collectors, mandrel-bent stainless steel construction, and optional catalytic converters.
• Estimated Price: $1,500 - $2,500 (depending on options)

Installation Tips and Considerations for Aftermarket Headers

Installing aftermarket headers can range from a relatively straightforward bolt-on process (for shorty headers) to a more complex undertaking (for long tube headers). Here are some key tips and considerations:

• Professional Installation: If you're not comfortable working on your car or lack the necessary tools, it's best to have the headers installed by a professional mechanic.
• Proper Tools: Make sure you have the right tools for the job, including sockets, wrenches, a torque wrench, and penetrating oil.
• Gaskets and Hardware: Always use new gaskets and hardware when installing headers. This will ensure a proper seal and prevent leaks.
• Exhaust System Modifications: Long tube headers often require modifications to the rest of the exhaust system to connect properly.
• Oxygen Sensor Extensions: You may need to purchase oxygen sensor extensions to reach the sensors after installing long tube headers.
• Heat Shields: Consider using heat shields or header wrap to protect nearby components from heat.
• Torque Specifications: Always torque the header bolts to the manufacturer's specifications to avoid damaging the header or engine.
• Check for Leaks: After installation, start the engine and check for any exhaust leaks. Address any leaks immediately.
• ECU Tuning: In some cases, installing headers may require an ECU tune to optimize engine performance and prevent issues like lean conditions.

Performance Gains and Dyno Testing After Header Installation

The performance gains you can expect from installing aftermarket headers will vary depending on several factors, including the type of headers, the engine's modifications, and the quality of the installation. However, in general, you can expect to see improvements in horsepower, torque, and throttle response.

Typical Performance Gains:

• Shorty Headers: 5-15 horsepower
• Long Tube Headers: 15-30+ horsepower

To accurately measure the performance gains from your header installation, it's recommended to perform a dyno test before and after the installation. A dyno test will provide you with a baseline measurement of your engine's horsepower and torque, allowing you to see exactly how much the headers have improved performance.

Remember that these are just estimates, and the actual performance gains may vary. However, with the right headers and a proper installation, you can definitely unlock more power from your engine and enjoy a more exhilarating driving experience!