The Guide to Upgraded Chevy C6 Corvette Headers. The Corvette C6 is widely regarded as one of the greatest American sports cars of all time. The C6 produced 430 horsepower and 424 lb-ft of torque from the factory after a mid-production conversion to the LS3 engine in 2008. Those are undeniably impressive figures. The real kicker, however, is the C6’s willingness to accept even more ponies from aftermarket additions. This is where upgraded C6 Corvette headers come into play.
The LS3 engine is optimized in a variety of ways in its factory configuration. Even with aftermarket parts, the stock LS3 intake manifold and head design give outstanding flow figures. However, there are some areas where the factory design could be improved. One of these areas is the design of the C6 Corvette exhaust manifold. Upgrading to performance headers is one of the cheapest improvements you can make to notice significant power and torque gains. Many of the restrictions in the factory C6 exhaust system begin at the exhaust manifold, and a good set of headers can significantly improve the breathing of your LS3 powerhouse.
The world of C6 headers is vast and can take a long time to explore. We’ll stick to the fundamentals in this article. We’ll go over what C6 Corvette headers are, the many types of headers available, and some recommendations at the end.
What Exactly Are C6 Corvette Headers?
Because of the huge performance benefits and better exhaust sound, headers are one of the first upgrades that most C6 LS3 Corvette owners consider. Discussions on LS3 C6 improved headers are common on forums and discussion boards, but the basics of what C6 Corvette headers are and how they work are rare.
C6 Corvette headers are the first exhaust component mated to the LS3 engine’s exhaust ports. As a result, they play a significant part in the exhaust flow leaving the engine. To clarify nomenclature, the phrase “headers” refers to an aftermarket exhaust manifold. Exhaust manifolds and headers serve the same purpose, but headers are usually more efficient due to their design.
The goal of replacing your C6 Corvette headers is to reduce the amount of effort required for the LS3 engine to release exhaust gases. The easier it is for exhaust gases to leave, the better the performance. In terms of performance, improved exhaust scavenging characteristics and lower backpressure are also important factors.
Unlike the stock C6 Corvette exhaust manifold, which collects exhaust gasses from all cylinders at the head and dumps them into a collector, C6 Corvette headers provide each cylinder with its own primary tube that transports exhaust gasses to the collector. This is crucial because primary tube length and diameter have a large impact on the overall efficiency of the headers.
Long-tube vs. Short-tube Corvette Headers
The topic of short-tube (or shorty) vs long-tube headers comes up in almost every header discussion. The distinction between the two is encapsulated in their names. C6 shorty headers have substantially shorter primary tubes that combine into a collector than long-tube headers. Long-tube headers, on the other hand, are the polar opposite.
The primary tube length differential between short and long-tube Corvette headers makes a major impact in how the LS3 engine operates. Exhaust gases are released into the headers in pulses as the LS3 in your C6 Corvette runs. The length of the primary tubes has a direct impact on where extra power is generated on the power and torque curves. Shorter C6 headers, in general, scavenge exhaust gasses faster by shortening exhaust gas pulses, which boosts horsepower and torque in the lower rev range. Long-tube Corvette headers, on the other hand, extend exhaust gas pulses, which moves horsepower and torque improvements higher up the rev range.
While short-tube C6 Corvette headers can produce noticeable gains, it is almost universally agreed that long-tube headers are the way to go on an LS3 C6 Corvette. Long-tube headers will produce the best results if you are only interested with performance, especially at high revs. While short-tube C6 headers will undoubtedly flow better than the factory C6 exhaust manifold, lower cost and better fitment are often more compelling reasons to choose shorties than performance gains.
High Flow Cats vs. Catless
Depending on the model year and where you live, the C6 Corvette came standard with two or four catalytic converters. C6 Corvettes from 2008 to 2011 had only two catalytic converters, however C6 Corvettes from 2012 and beyond have four cats in the mid-pipe. The more cats that are placed into the exhaust system, the more restrictive the system as a whole becomes. Catalytic converters are installed between the exhaust manifold and the X-pipe in factory C6 Corvettes. While some short tube headers allow you to keep the factory cats, most long tube headers will necessitate the installation of new cats.
When it comes to catalytic converters for Corvette performance headers, there are normally two alternatives. You have the option of running C6 headers with or without catalytic converters. Before we go, it is vital to note that becoming catless is illegal in the majority of US states. Because of this, catless C6 headers and X-pipes are primarily an off-road improvement. You won’t be able to pass an emissions test with catless long-tube headers. Having said that, catless Corvette headers and X-pipes will produce the greatest performance benefits.
Another possibility is to locate a set of long-tube C6 headers with high-flow catalytic converters. The majority of aftermarket catted C6 Corvette header choices include an X-pipe as well. The cats are typically relocated by including them within the X-pipe. While the gains may not be as dramatic as with a fully catless header option, high-flow catted Corvette headers are the better option overall. They’ll keep your Vette’s emissions legal while also giving significant horsepower and torque increases.
The Advantages of Upgraded C6 Corvette Headers
The advantages of upgrading your C6 Corvette headers are numerous in terms of performance and sound. Obviously, the horsepower and torque output from an LS3 header upgrade can vary greatly. As previously discussed, there is a difference in power increases and where in the rev range power is created depending on the type of header used and whether a high-flow or catless option is used. Here are some of the most obvious gains you can expect from upgraded C6 Corvette headers:
Gains in LS3 Corvette Long-Tube Header:
- (Catted) 10-20 hp gain with comparable torque gain with tuning
- (Catless) 20-30 hp gain with comparable torque gain with tuning
- Significant power gain in the mid-to-high rpm range between
4,500-6,000 rpm - Backpressure has been reduced.
- Lowering the temperatures of the exhaust gases
- improved exhaust scavenging capabilities
- Exhaust sound has been improved.
Gains in LS3 Corvette Short-Tube Headers:
- (Catted) 5-15 hp gain with comparable torque gain
- Significant increase in power in the low-mid rev range of 1,500-3,500 rpm.
- Backpressure has been reduced.
- Lowering the temperatures of the exhaust gases
- improved exhaust scavenging capabilities
- Exhaust sound has been improved.
- HP Gains for C6 LS3 Corvette Headers
Looking at the data above, it is evident that long-tube C6 headers are the way to go if performance is the aim. The enhanced power gains from long-tube headers are due to the influence of primary tube length and diameter on exhaust scavenging. Most long-tube headers are precisely constructed to interact with exhaust gas pulses in such a way that as much negative pressure as possible is created in the headers to pull exhaust gas out of the cylinder as quickly as possible. Long-tube headers excel at this “scavenging” effect, which is essential for greater performance.
Backpressure is another important element that improved Corvette headers can help to minimize. Backpressure is created by resistance in the exhaust system, which might be caused by catalytic converters or by piping diameters that are not optimum. C6 headers, both long-tube and short-tube, can reduce backpressure by reducing the amount of resistance that exhaust gases face. As a result, horsepower is enhanced.
Long-tube Corvette headers, in general, do a better job of enhancing exhaust scavenging and lowering backpressure, resulting in larger performance benefits. This is particularly true with catless long-tube headers. Having said that, there are justifications for short-tube headers as well. They are usually less priced, simpler to install, look nice in the engine bay, and improve exhaust tone. However, if peak performance is the goal, they are not the way to go.
Best Corvette C6 Headers
After we’ve covered the fundamentals, let’s look at some of the best C6 Corvette header options on the market right now. Because headers are such a popular modification for the LS3 C6 Corvette, there are plenty of good options. This is true for both catless and high-flow catted headers. While long-tube header options are by far the most popular, we will also include a short-tube option.
1 3/4″ C6 Corvette Kooks Headers with High Flow Cats
Price: $2,445.30
Compatibility: LS2 C6 2005-2008, LS3 C6 2009-2013
Long-Tube Style
You can’t scroll for more than about 10 seconds in most C6 Corvette header conversations without seeing the name “Kooks” arise. They are a well-known manufacturer for its high build quality and attention to detail. For the past 50 years, Kooks has focused on performance headers and exhaust components for American racing applications.
The Kooks C6 Corvette Long-Tube header set includes everything you need to upgrade your C6 exhaust. The package includes a set of T304 stainless steel long tube headers with large 1 34″ primaries, a high-performance X-pipe with high-flow cats, new gaskets, O2 extensions, and exhaust clamps, and a high-performance X-pipe with high-flow cats. In a nutshell, it includes everything you need to get started.
In addition to 1 34″ primary tubes, Kooks also offers 1 7/8″ and 2″ primary tubes for customers seeking to transition to forced induction in the future. The 1 34″ recommendation is based on good naturally aspirated drivability. Large main tubes will provide little to no performance improvement without forced induction.
C6 Corvette 1-7/8″ Long-Tube Catless Headers by Texas Speed & Performance
Price: $1,109.84
Compatibility: LS2 C6 2005-2008, LS3 C6 2009-2013
Long-Tube Style
Unlike the Kooks long-tube option stated above, the Texas Speed & Performance C6 Corvette Long-Tube kit is only intended for track use and does not include any cats. Texas Speed, like Kooks, has a long history of producing LS and LT1 performance parts. Their C6 long-tube header set combines optimum performance with a low price to provide the perfect package.
The Texas Speed set is practically unsurpassed in terms of build materials and structure. The headers are made of 304 stainless steel and CNC mandrel bent for maximum airflow efficiency. In addition to the headers, the kit includes a 3″ off-road catless C6 Corvette X-pipe. The headers and X-pipe work together to provide one of the most efficient and least-restrictive C6 exhaust systems on the market.
Texas Speed believes that when combined with an appropriate tune, their header and X-pipe combo can produce a 20-25whp boost. That is a significant increase in power that you will undoubtedly feel.
Hooker Blackheart C6 Corvette Short-Tube Headers 2005-2013
Price: $1,010.95
Compatibility: LS2 C6 2005-2008, LS3 C6 2009-2013
Short-Tube Style
One of the most difficult issues with long-tube headers is engine compartment and under-vehicle clearance. Most large-diameter long-tube Corvette headers require considerable modification to fit in place of the exhaust manifold. Long-tube headers will usually drag over speed bumps and road irregularities. These are the main reasons why short-tube headers are significantly easier to install and maintain. The Hooker Blackheart set is an excellent alternative for a decent C6 short-tube solution.
One of the key design advantages of the Blackheart short-tubes is maximum exhaust velocity, which bodes well for power in the low-mid rev range. The Hooker Blackheart set, like the majority of the C6 headers on our list, is composed of high-quality 304 stainless steel for longevity and superb thermal dynamics. The fact that the Blackheart shorty header design was developed to work directly with current factory hardware is one of its features.
Hooker Blackheart shorties hook up to the factory catalytic converters, unlike long-tube C6 Corvette headers that force you to get creative with cat solutions. They also include all of the hardware required to work with the factory O2 sensor. While Blackheart shorties are not yet CARB approved, they are on the way. With Blackheart headers installed, your C6 Corvette is likely to pass emissions. Hooker, on the other hand, suggests that they be used solely off-road.
Related : The Guide to Upgraded Chevy C6 Corvette Headers
Long-Tube LG 05-13 Corvette Super Pro LS3 Headers
Price: $1,706.36
2005-2013 C6 Corvette Base/Z51/Grand Sport LS2/LS3 V8 Compatibility:
Long-Tube Style
The LG header kit is a good alternative for anyone searching for some customizability in a C6 Corvette long-tube header from yet another well-known company in the LS world. The LG Super Pro kit is available in a range of configurations to meet your specific requirements. It is available with or without enormous 3″ high-flow cats optimized for lowest resistance. In addition to multiple cat configurations, you have the option of choose between 1 34″ or 1 7/8″ primary runners, which can fit present or future C6 upgrades.
The LG Super Pro kit is adaptable and will work with both LS2 and LS3 C6 Corvettes. The LG kit, like some of the other alternatives on this list, includes a 3″ performance X-pipe. The collectors are constructed with a 3″ merge design for maximum scavenging performance. Some long-tube C6 headers sacrifice low-end torque for high-rpm performance. The LG kit was designed to deliver the highest overall performance without sacrificing low-rpm torque.
Summary of C6 Corvette Header Upgrades
Upgraded headers are one of the most noticeable and talked-about upgrades you can make to your C6 LS3 Corvette. The advantages over the conventional C6 exhaust manifold are significant in terms of improving exhaust flow and offering greater exhaust scavenging, which correlates to improved overall performance. Because upgraded C6 Corvette headers are such a popular modification, there are numerous aftermarket options. The goal is to identify the correct set of headers for your requirements.
The catalytic converter layout is one of the most significant aspects. While catless C6 headers will undoubtedly provide the best performance, they do have some drawbacks. Catless headers are exclusively intended for racing and will cause your C6 to fail an emissions test. A set of long-tube C6 headers with high-flow cats is your best choice for maximum gains while being road legal.
In the LS world, long-tube Corvette headers are the standard. This is due to their greater scavenging and backpressure-relieving capabilities. Long-tube headers offer the finest mid-high rpm performance, but they are frequently more expensive and more difficult to install than short-tube headers. While shorty LS3 headers aren’t the best option for power gains, they’re popular because of their ease of installation, compatibility with factory catalytic converters, improved exhaust tone, and lower price.
