LS2 headers upgrade
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Chevy LS2 Headers Upgrade Guide

Chandler Stark

Meet Chandler

Chandler is an automotive expert with over a decade of experience working on and modifying cars. A couple of his favorites were his heavily modded 2016 Subaru WRX and his current 2020 VW Golf GTI. He’s also a big fan of American Muscle and automotive history. Chandler’s passion and knowledge of the automotive industry help him deliver high-quality, insightful content to TuningPro readers.

GM/Chevy first introduced their glorious LS2 V8 engine in 2005, putting it in models like the C6 Corvette, Pontiac GTO, and SSR truck. Within a few years, they started putting versions of the LS2 inside a wider range of applications. This included several trucks and SUVs like the Chevy Silverado, Chevy Trailblazer SS, and GMC Sierra and Yukon. The engine produced between 300-400 horsepower and 360-400 lb-ft of torque, depending on the application.

While 300-400 horsepower from the factory certainly isn’t slow, the LS2 has so much more potential. These engines can easily gain 30-50 horsepower without breaking a sweat, and they can take a ton more. One of the top mods for LS2 powered cars, trucks, and SUVs is swapping out the stock exhaust for a set of headers. Upgraded LS2 headers will add horsepower and torque, improve throttle response, and really unlock the GM/Chevy 6.0 L engine. Of course, it’ll also really let the LS2 roar much louder than before.

This guide will cover the top options for upgrading your LS2 headers. We’ll take a look at the most well reviewed and well respected LS2 headers within the GM/Chevy community, and analyze them by cost, performance, and craftsmanship.

*Keep in mind, the LS2 was available in a pretty wide range of vehicles. This guide is meant to cover headers for as many LS2 equipped vehicles as possible. However, still make sure you confirm fitment with your specific vehicle model before making any purchases.

LS2 headers upgrade
Credit: American Racing Headers

What is a GM/Chevy 6.0 LS2 Header?

Headers are the part of an exhaust system that attaches directly to the exhaust ports on the LS2 engine. From the factory, they are typically called exhaust manifolds, and the term headers indicates something aftermarket. Enthusiasts use them when looking to increase the power output of their LS2 engine.

Headers collect the hot exhaust gasses as they are pushed out of the engine and direct them through the rest of the exhaust system. Due to being bolted directly to the engine, design and construction are incredibly important to prevent leaks and cracking. For stock power levels and applications, the OEM exhaust manifolds are capable of adequate performance. However, for anyone looking to increase their performance or get the most out of their other bolt-ons, aftermarket headers become very useful. Aftermarket headers are usually made from 304 stainless steel and have wider diameter piping than stock exhausts.

You want headers that provide good flow with as little turbulence as possible, while reducing weight over the stock exhaust. Exhaust gas turbulence is created by poorly thought out designs that introduce large inopportune bends and joints, which impedes flow. This diminishes the effectiveness and leads at times to reversion.

Reversion is a phenomenon where hot exhaust gasses are pushed back into the combustion chamber, robbing the engine of clean and cool air. A good header should open the exhaust flow, while reducing overall weight and exhaust gas temperatures and eliminating reversion.

GM/Chevy 6.0 Long-tube vs Short-tube Header

There are two types of aftermarket headers that are commonly available for the LS2 engine, long-tube headers and short-tube headers. As their names suggest, the primary difference between the two of them is their length. Long-tubes extend much further back than the short-tubes (also called shorties) and usually either remove the catalytic converters or come with high-flow cats. Short-tubes keep the cats in place, but we’ll get into more on that below.

Long-tube headers will undoubtedly offer better overall performance gains than short-tube headers, particularly in the mid-range and top-end of the power band. Short-tube headers will help with performance on the low-end, but at the expense of top-end power. They also produce less overall power than long-tubes everywhere in the power band. The best shorty LS2 headers will probably still be outperformed by low-quality long-tube 6.0 L headers.

Chevy LS2 Catted vs Catless Header Considerations

One of the most important decisions you will have to make when picking out LS2 headers is catted or catless. The stock LS2 exhaust system has two catalytic converters located very close to the stock exhaust manifold. The purpose of catalytic converters is to reduce emissions from the engine which contribute to climate change. However, catalytic converters also impede exhaust flow, meaning they reduce horsepower.

LS2 short-tube headers only replace the area between the engine and the cats, whereas long-tube headers also replace the area with the stock cats. Some long-tubes have high-flow cat replacements built in, while others are completely catless.

If you do not want to touch your cats, then short-tube LS2 headers are your only option. If you are okay with either removing them or switching to high-flow cats, long-tube headers are the better option. As we stated, long-tube headers will give you the best performance, even if they are catted.

For most people, the best middle ground is going to be long-tube headers with high-flow cats. These still wake up the engine and increase horsepower, but they also stay legal for the most part.

Catless LS2 Headers Legality

An important consideration is legality. Removing your catalytic converters is a violation of many state and local laws, and can also run afoul of the EPA’s Clean Air Act. Catless exhausts are not street legal in the vast majority of the U.S. due to state emissions laws. This does not apply to vehicles that are strictly used at the race track.

Catted long-tubes will generally pass the sniffer test for emissions, and in many places are considered street legal for use. However, there are also some state (namely California) and local laws that prohibit any change to the cats, meaning even high-flow versions will not pass visual inspection. Make sure you consult and follow all applicable local, state, and federal laws before committing to any specific headers.

GM/Chevy LS2 Header Upgrade Benefits

Most enthusiasts looking at header upgrades are concerned with power gains, but there are several other benefits as well. Some of the benefits of upgraded LS2 headers are:

  • +5-30 horsepower
  • +5-25 lb-ft of torque
  • Reduced back pressure & reversion
  • Lower exhaust gas temperatures (EGTs)
  • Improved exhaust scavenging
  • Louder/Improved exhaust tone and volume

A pair of Gm/Chevy 6.0 L long-tube headers will net gains of about 15-30 horsepower by themselves. You can expect about a 5 horsepower difference between catted and catless versions. Shorty LS2 headers will gain 5-15 horsepower.

One of the biggest advantages of header upgrades is reduced back-pressure and increased scavenging effectiveness. OEM headers are less effective outside of stock power levels and are usually made with cast iron. Aftermarket headers are purposefully designed to weigh less, reduce back-pressure, and increase scavenging at higher than factory power levels.

Reducing back-pressure lowers EGTs and increases scavenging, which both have several benefits. Keeping EGTs down prolongs engine life and keeps performance high. Increased scavenging and reduced reversion means the dirty exhaust gasses are removed and clean air can enter the combustion chamber. Which leads to bigger and more sustained power.

Of course, you’ll also hear a very clear audible difference in your car, truck, or SUV from installing new headers. Short tubes won’t be as loud as long-tubes, but will produce a noticeable difference. Long-tubes will raise your decibel level several points, with catless exhausts being louder than catted. The volume will be louder, and the tone will also get deeper and more aggressive from catless long-tube headers on the LS2.

Chevy 6.0 Header Horsepower and Torque Gains

As we mentioned, long-tube LS2 headers will gain about 15-30 horsepower and 10-25 lb-ft of torque, and shorties will net about 5-15 horsepower and 5-10 lb-ft of torque. The entire power band will also be increased much more on long-tubes vs shorties. The removal/replacement of the stock cats with larger diameter piping seals the win for the long-tubes.

Not every LS2 equipped vehicle will see the same exact gains, as there are many other facts like the specific engine variant being used, octane rating, and whether any other mods (like a cold air intake) have been done. But generally, you should see at least 15 horsepower out of long-tubes on lower quality gasoline and without other mods. Shorties will pick up at least 5 horsepower, and they max out at about 15 horsepower on the high end.

Headers are a great upgrade for getting a little extra power and volume out of the Gm/Chevy 6.0 L without adding forced induction. They are great when coupled with mods like intakes and cat backs, and enthusiasts can really tailor their exhaust note to their choice by exploring all of the different combinations.

GM 6.0 X-pipe vs H-pipe

If you are going with LS2 long-tube headers, you will have to choose between either an x-style mid-pipe or h-style mid-pipe. The difference is with the h-style pipe, the two headers never intersect and stay completely independent. On x-style mid-pipes, the headers will merge together before splitting off again for dual mufflers.

X-style pipes out perform the h-style pipes, but only barely. The x–style does allow for increased flow, but has shown to only translate into maybe 5 horsepower at the most. H-pipes generally allow for better low-end performance, while x-pipes tend to make a difference at the top of the power band. X-pipes also sound more high pitched than the more traditional hot rod sounding h-pipes.

The more popular option tends to be the x-pipe, but it really comes down to personal opinion. Since sound is one of the biggest factors, you’ll probably want to hear both of them to make a good comparison.

Top 4 GM/Chevy LS2 Headers

Now let’s get into the top LS2headers. This list is far from an exhaustive list of header upgrades. There are tons of great options that are just too numerous to list. Make sure to keep in mind that fitment will vary by year, make, and model. Always double check fitment before purchasing any headers.

We’ve tried to focus on headers that are applicable to as many GM/Chevy models and years as possible. We’ve listed both long and short-tube headers that offer the best balance of price, quality, fitment, and performance. Let’s get started. Keep in mind, most LS2 headers will need a custom exhaust back to the muffler as they won’t fit the stock pipes.

Here are the top 4 GM/Chevy LS2 Headers:

  • American Racing Headers
  • Stainless Works
  • Kooks Headers
  • Texas Speed and Performance
LS2 headers upgrade
Credit: Kooks Headers

1) American Racing Headers LS2 Long-tube Headers

Style: Long-tube, Catted & Catless

Purchase Links:

2005-2006 Pontiac GTO LS2 American Racing Headers

2006-2009 Chevrolet Trailblazer SS LS2 American Racing Headers

Our first recommendation for LS2 headers are from American Racing Headers. ARH is one of the most respected exhaust manufacturers in the industry, and they have a great reputation for their work with the LS series. They offer both 1-¾” and 1-⅞” primaries and merge collectors, and make all of their exhausts from 304SS. ARH also has either catted or catless options, depending on what you want.

ARH offers a wide variety of long-tube headers for the LS2 series. As you can see above, they make headers for the C6 Corvette, GTO, Trailblazer SS, G8, and Caprice PPV. ARH is going to be one of the more expensive brands on the market, but you are definitely paying for quality. All ARH products are built 100% in the USA and hand tig welded.

ARH claims gains of anywhere from 20-40 wheel-horsepower, depending on the application. Real-world gains are probably closer to 30 horsepower with just the headers, but with tuning and an intake you will definitely see a bigger bump. We’d recommend the ARH out of all of our suggested headers, as they have the best reputation for customer service and quality.

2) Stainless Works Long-tube Header for LS2

Style: Long-tube, Catted & Catless (CTS-V only)

Purchase Links:

2006-2007 Cadillac CTS-V LS2 Stainless Works Headers

2007-2013 GM/Chevrolet Sierra/Silverado 1500 LS2 Stainless Works Headers

Next up are the LS2 headers from Stainless Works. Like ARH, Stainless works has an excellent reputation in the exhaust world, and their LS2 products are very well reviewed. Stainless Works isn’t the biggest volume manufacturer, but they definitely provide good quality.

Stainless offers headers for the GTO, CTS-V, Trailblazer SS, and Sierra/Silverado. For the LS2 headers, you also have to buy their cat-back or get a custom one built, as it does not fit the stock exhaust. Most of their exhausts come with high-flow cats as the only option. The exception is the CTS-V fitment headers which are only available catless.

Stainless Works claims gains of more than 50 wheel-horsepower and 45 wheel-torque with their headers and a tune. Real world performance without a tune is probably closer to 30 horsepower, similar to the ARH LS2 headers. Pricewise, Stainless is going to be similar to ARH, and quality is similar, too.

3) Texas Speed and Performance Long-Tube Headers for LS2 Trucks/SUV/C6/GTO

Style: Long-tube, Catless

Purchase Links:

2007-2013 GM/Chevy Trucks LS2 Texas Speed and Performance Headers

Next up are the Texas Speed and Performance LS2 headers. These are our budget recommendations for the LS2, but that doesn’t mean they are low quality. Texas Speed and Performance is a very reputable company that makes exhausts for a wide range of manufacturers and applications.

Their LS2 exhaust series are all catless and meant for the race track, except the G8 headers which can be had with cats. They are all made from 304SS and use mandrel bends. Price wise, the TSP headers are going to be ½ to ⅓ the price of our other recommendations (except Kooks).

TSP claims gains of around 20 wheel-horsepower, which is probably not too far off from real world performance. The TSP headers are a solid option if you are looking to save a little money on your purchase while still retaining good quality.

4) Kooks Headers LS2 Headers

Style: Long-tube & Short-tube, Catted & Catless

Purchase Links:

2005-2006 Chevrolet SSR LS2 Kooks Headers

2007-2013 GM/Chevrolet 1500 Truck LS2 Kooks Short-tube Headers

Our final recommendation for LS2 headers is from Kooks Headers, one of the top brands in the industry. Kooks have long been associated with quality exhaust parts, and their headers are known to be exceptional.

Kooks makes headers for the widest variety of LS2 powered vehicles, including the SSR, Trailblazer SS, Silverado, Yukon, Suburban, Caprice PPV, and more. They offer both catted and catless options, and for 2007-2013 GM/Chevy trucks there are short-tubes available. Like the others, Kooks uses 304SS, and it is made completely in the USA.

Expected power gains with the Kooks headers are 20-30 horsepower for the long-tubes, and 5-15 horsepower for the short-tube option. They perform very well on both trucks and cars, and are used on some of the top LS2 builds. Price wise, the Kooks are on the bottom end, but trust us that is not indicative of worse quality. Kooks has a fantastic reputation, and their headers have excellent quality and performance.

GM/Chevy LS2 Header Upgrade Summary

The GM/Chevy LS2 is an incredible engine, but it is capable of so much more performance than it is setup with from the factory. Just adding a good set of headers will really wake up the LS2. You’ll see gains in power and performance, and you’ll be able to hear the mighty LS2 roar at the top of its lungs. Expect to get 15-30 horsepower from long-tubes, and 5-15 horsepower from short-tubes on the GM/Chevy 6.0 V8.

We looked at some of the top options available on the market, including options from American Racing Headers, Stainless Works, Texas Speed and Performance, and Kooks Headers. Of all of them, we’d probably go with the ARH due to their quality, but if you’re on a budget the Kooks are hard to pass by. Either way, any of these headers will definitely be solid choices.

What’s your experience with LS2 headers? Are you considering any?

Leave a comment and let us know!

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