Chevy’s 6.0 l LS2 small-block V8 is one of the most reliable power plants for starting a build. Featured in the 2005-2007 Corvette, SSR, Trailblazer SS, and Pontiac GTO, among others, the LS2 has been a popular choice for drag racers and road racers for many years. It’s virtually indestructible on moderate builds, makes power pretty easily, and has a massive aftermarket support community.
This guide will cover the top 5 LS2 upgrades for making more horsepower. Every build has to start somewhere, and we’re here to help you get your new LS2 project off the ground. We’ll talk a little bit about the LS2 engine itself, explain its power limits, and then give you our top LS2 mod recommendations.
Keep in mind, the LS2 was available in a pretty wide range of vehicles. This guide is meant to cover all vehicles with the LS2. Make sure you confirm fitment with your specific vehicle model before making any purchases.
LS2 Engine Info
Previously, we took an in-depth look at the LS2 engine with our LS2 engine guide. We’re just gonna run through the basics here, so make sure you take a look at that article if you want the full breakdown.
General Motors introduced the LS2 in 2005, putting it in the Chevrolet Corvette, SSR, Trailblazer SS, and Pontiac GTO. It was the first engine of GM’s Gen IV small-block motors. The engine made 400 horsepower and 400 lb-ft of torque in the Corvette, and was immediately praised by owners. Though it had a relatively short production run, lasting only until 2009, it produced several variants which lasted much longer.
The LS2 is a 6.0 L naturally aspirated V8 engine. It does not have Variable Valve Timing (VVT), and is an old school pushrod OHV, 2 valves per cylinder design. The block and head are both made from aluminum, and the corvette has a different oil pan than other LS2s. The LS2 head is the GM-cathedral port style of head, which is known for better low-end torque, but flows sub-optimally at higher RPM.
The LS2 Variants
Branching off from the LS2, GM created three variants: the L76, L77, and L98 V8 engines. The L76 has Active Fuel Management (AFM), VVT, and the LS rectangular-port style cylinder head. However, it has lower profile cams and a lower compression ratio.
The L77 has flex-fuel capabilities and AFM, but does not have VVT. The L98 has neither flex-fuel, AFM, nor VVT. Both the L77 and L98 use the same higher flowing LS3 head with rectangular ports as the L76.
While any of these are great motors to start with, most people opt to build either the original LS2 or the L76 variant. The L76 has the less than desirable AFM and cams, but does have VVT and rectangular port heads. The LS2 has the cathedral-port head and better cams, but doesn’t have VVT. Unfortunately, VVT can’t be added to the LS2, and the cams on the L76 are limited due to the AFM.
This article will focus on LS2 upgrades, but much of the same knowledge can be applied to the L76, L77, and L98 engines.
Modded LS2 Engine Power Limits
Regardless of the variant, the LS2 engines all have pretty robust power limits – like the rest of the LS-family. It’s widely considered that the LS2 has stronger internals than the LS1, which is already pretty stout itself.
The LS2 is capable of taking more than 800+ wheel-horsepower on the stock block without any issues. There have been many stock LS2 blocks that have pushed into the 900+ whp territory without issues, but that’s risky if you ask us.
Past the 550 wheel-horsepower mark you will want to invest in forged pistons and rods, as well as head studs. Again, this isn’t a hard limit like with the LS2 block, as there are many stock LS2 builds pushing well into the 600 and 700+ whp range. For reliability, however, you’re going to want stronger pistons and rods if you’re pushing past 550 whp.
Chevy LS2 Engine Domestic Vehicle Applications
Here is a list of all the domestic vehicles the LS2 and its variants were put in by GM. The L98 never appeared stateside.
LS2 Vehicle Applications
- 2005–2007 Chevrolet Corvette
- 2005–2006 Chevrolet SSR
- 2005–2006 Pontiac GTO
- 2006–2007 Cadillac CTS-V
- 2006–2009 Chevrolet TrailBlazer SS
- 2008–2009 Saab 9-7X Aero
L76 Vehicle Applications
- 2007–2013 Chevrolet Avalanche
- 2007–2009 Chevrolet Silverado 1500
- 2007–2009 Chevrolet Suburban 1500
- 2007–2009 GMC Sierra 1500
- 2007–2009 GMC Yukon XL
- 2007–2009 Pontiac G8 GT
L77 Vehicle Applications
- 2011–2017 Chevrolet Caprice PPV
Top 5 LS2 Upgrades
Our top 5 LS2 upgrades are:
- Cold Air Intake
- Long-tube Headers
- Cylinder Head
- ECU Tuning
We’ll get much more in-depth down below, but here’s a basic summary of the top 5 LS2 upgrades.
Simple bolt-on mods like a cold air intake and long-tube headers are great first mods for an LS2 build. They help improve airflow in and out of the engine while (slightly) improving gas mileage. You’ll notice a good spike in power after installing these, and you’ll really start to hear your LS2 roar.
Next up is going to be to upgrade the LS2 cylinder head. As we mentioned earlier, the LS2 uses the LS cathedral-port style of cylinder head. While these are good for low-end torque, they really struggle for good flow in the higher RPM range. You’ll want to either get your stock LS2 head ported or switch to the rectangular style.
The LS2 camshafts are also a very common area to upgrade early in LS2 builds. The stock LS2 cams have 0.520” intake and 0.521” exhaust lift, meaning they have some definite room for more if you want bigger power. Camshaft choices are important, as you’re going to have a trade-off between low-end torque and top-end performance. The right cam will get you a good tradeoff, and give you torque where you need it and power when you want it.
Finally, ECU tuning is our final LS2 upgrade. While it might not seem important, tuning can make the difference between a good and great engine build. With tuning, you’ll be able to have optimized ignition timing and air-to-fuel ratios, as well as other parameters to help you take advantage of all your mods. If you’re going to be spending hundreds in bolt-ons, you’ll want to make sure to maximize your gains from them.
1) LS2 Cold Air Intake Upgrades
One of the best upgrades for pretty much any naturally aspirated engine is going to be a cold air intake. The LS2 is no different, and can see gains of 10-15 horsepower from just an intake alone. The stock intakes on most LS2 equipped vehicles are pretty restrictive and strangles horsepower for builds at higher RPM.
The purpose of a cold air intake is twofold: one, it helps to grab cooler air from outside of the engine bay for better performance by relocating the filter placement. Two, it cuts down on the restrictiveness of the OEM intake.
While the stock intakes generally perform okay, if you add any other bolt-ons, like long-tube headers, it quickly becomes overmatched. Adding a freer flowing intake will improve throttle response, top-end power, and increase the engine noise. It also makes your engine bay look much better and more aggressive.
Best LS2 Cold Air Intakes
While it’s going to depend on your specific model for the best intake, we typically recommend a cold air intake as one of the first mods you do. One of the big decisions you’ll have to make is closed vs open airboxes. Generally, open airboxes are more susceptible to heat soak, but they allow for better airflow. Closed airboxes cut off some airflow, but they also mitigate engine heat soak for longer.
For the Corvette, since the intake is already at the front of the bay, it’s pretty difficult to relocate the filter while improving flow. For that reason, on the Corvettes we recommend the very popular Vararam Ram Air intake. While it is a ram style intake, and not a true cold air intake, it performs very well on the C6 Corvette.
They claim gains of up to 35-40 horsepower, but it’s more realistic to cut that in half at closer to 10-20 horsepower. Still, the Vararam is very popular in the Corvette community and is a proven intake.
For the GTO LS2, we recommend the Cold Air Inductions GTO cold air intake. This intake completely replaces the stock LS2 GTO intake for one lighter and less restrictive. It includes a closed and insulated aluminum airbox and a 4” intake tube. CAI claims gains of up to 16 whp with just their intake alone.
Buy Here: Chevrolet Corvette C6 Vararam LS2 Intake
2) LS2 Long-tube Header Upgrades
Our next suggestion for LS2 upgrades is going to be long-tube headers. The stock cast-iron headers are incredibly restrictive, heavy, and can be prone to cracking over time. For any serious build, upgrading the long-tube headers is an absolute must.
Long-tube headers replace the OEM exhaust manifold and exhaust back to the mufflers. They are wider than OEM, typically made out of lighter 304 stainless steel, and are designed for optimal exhaust flow. All of this combines to reduce back pressure and reversion, while increasing exhaust scavenging.
The reduction in back pressure allows for better exhaust flow. Increased exhaust scavenging and reduced reversion means exhaust gasses are removed quicker and more clean air can enter the combustion chamber. This leads again to bigger and more sustained power.
You’ll also undoubtedly get a big bump in exhaust volume from long-tube headers. As you might expect, the big increase in piping and optional cats really turns up the sound from the LS2.
Best LS2 Upgrades for Long-Tube Headers
LS2 long-tube header upgrades generally fall into one of two categories: catted or catless. Catless systems will produce a little more power, but they are also not emissions compliant and will not pass inspection.
We recommend going with catted headers, because the power difference is pretty minimal and they are much better for daily drivers. Catted exhausts will be a little quieter, but they also don’t produce the horrible smells from catless exhausts. You should still be able to hit whatever your power goals are, even with a catalytic converter.
Our recommendation on LS2 long-tubes are going to be from American Racing Headers. ARH is a tried and tested name in the exhaust industry, and they have been producing solid long-tubes for many years. Their LS2 exhaust systems are available in several different primary sizes and are all made from 304 SS. They have beautiful merge collectors that really optimize flow and scavenging. You should see gains of 10-25 whp with long-tube headers on the LS2 by itself, and more with tuning.
Buy Here: Pontiac GTO ARH Long-tube Headers
3) LS2 Cylinder Head Upgrades
Next on our list of LS2 upgrades is the LS2 cylinder head. As we have mentioned before, the LS2 cathedral-port style cylinder head is not optimal for higher RPM flow. While it does a great job of providing low-end torque, if you’re wanting a lot of top-end horsepower you’ll want something different.
One option is to port the factory LS2 head, which does help a little bit, but you’re always going to be limited by the port-style. The LS3 cylinder head fits directly onto the LS2, though it requires a new intake manifold, but it is massively superior to the LS2. The LS3 has the LS rectangular style ports, which are much better for horsepower on the top-end.
Top LS2 Cylinder Head Upgrades
For LS2 head upgrades, we’re going to recommend the Livernois Motorsports Stage 2 or Stage 3 head. Your power goals will determine which one you want to go with, as Stage 3 will promote more power over Stage 2. We’re recommending their LS3 head for the LS2, but they also make specific LS2 heads as well.
You want to make sure you fit your head to your power goals. Too small and you’ll still be restricted and hitting a choke point too early. Too big and you’ll lose too much low-end performance to make up for it on the top-end.
The Livernois Motorsports LS3 head is 100% 5-axis CNC machined in America. Livernois has been at the top of the industry for the LS-series of engines for decades, and their LS3 head is very highly reviewed.
4) LS2 Camshaft Upgrades
Camshafts are going to be our next recommendation for LS2 upgrades. The stock cam is fine for stock power levels, but if you’re looking at other bolt-ons then upgrading the cam is a good idea, too. The stock LS2 are not too aggressive for big power, and are really meant for stock power levels.
When upgrading camshaft, the thing you are going to want to pay the most attention to are duration and lift. A higher lift means the valve opens wider, which means more air can get into the engine for more power. A longer duration means the valve will be open longer, again allowing for more air to enter the engine.
The trade-off for longer duration and higher lift cams is more top-end power at the expense of low-end torque. Especially if you’re building your daily driver, you’ll want a good balance between low-end torque and top-end horsepower. This will make your car still drivable at low engine loads in traffic, while allowing you to toast some rubber when you want.
Best LS2 Camshaft Upgrades
For LS2 camshaft upgrades we have three recommendations, all of them for different build levels. The stock LS2 cam has 0.520” intake and 0.521” exhaust lift, with an intake duration of 204 @ 0.050” and exhaust duration of 211 @ 0.050”. GM designed them for average performance with lots of low-end torque.
The Chevrolet LS Hot Cam is a popular upgrade for the LS2. The cam measures at 0.525” intake and 0.525” exhaust lift, a small but noticeable increase over stock. The duration is also longer, with an intake duration of 219” @ 0.050” and exhaust duration of 228” @ 0.050”. This will give you a mild increase in power while still providing lots of low-end torque.
For the next steps up, we recommend the Livernois Motorsports Stage 2 and Stage 3 LS cams. The Stage 2 cam has a lift 0.595” and the Stage 3 lift is 0.612”. The Stage 2 duration is 232 @ 0.050”, and the Stage 3 lift is 224 @ 0.050”. As you can see, both of these offer some serious potential for top-end power gains. Check out this LS2 MotorTrend article where they throw an LS2 with some Livernois Motorsports Stage I and II cams on the dyno and see just how powerful they are.
Buy Here: Chevrolet LS Hot Cam for LS2 Upgrade
Purchase Link: Livernois Motorsports Stage 3 Camshaft for LS2 Upgrade
5) ECU Tuning for the LS2
Our last recommendation is also one of the most important: LS2 tuning. Just by itself, tuning will give you a healthy 20-30 horsepower increase. In addition, while all of the above upgrades are by themselves powerful, to really take advantage of them you’re going to want to add tuning. Tuners can optimize parameters like ignition timing, air-to-fuel ratios, and fuel pressure to get the most out of your bolt-on mods.
In addition, while tuning can help maximize the power from your mods, it can also help them run safely. When you change the intake and exhaust flow on an engine, the air-to-fuel ratios inevitably change, too. While most upgrades leave the ratios in a safe area, it’s impossible to confirm that without tuning. To make sure your engine is running healthy with your mods you’ll definitely want a tuner to take a look at the car.
Best LS2 Tuners
For LS2 tuning you have a few options, either custom or canned tuning. Custom tuning is far superior to canned tuning, because it allows your tuner to customize his work to your specific engine and your specific atmospheric conditions.
Canned tunes are one-size fits all tunes that are meant to work in any environment. Custom tunes, on the other hand, provide specific adjustments for things like elevation, humidity, and air quality. Obviously, someone living in California and someone living in Wisconsin aren’t going to have the same atmospheric conditions. So to truly optimize your tune for your car, you need to go custom.
Our recommendation for custom tuning on the LS2 Corvette and LS2 GTO are from Livernois Motorsports. They offer custom tuning with their own proprietary MyCal tuning device. For the Corvette, Livernois claims gains of 19 horsepower and 23 lb-ft of torque on 93 octane. On the GTO, Livernois claims gains of 19 horsepower and 22 lb-ft of torque on 93 octane. That’s just with tuning alone, and they can compensate for some of your other mods, too. Add in the other suggested upgrades and you’ll have a 500+ horsepower beast with tuning.
Buy Here: Livernois Motorsports LS2 GTO Tuning
Top LS2 Engine Mods Conclusion
Overall, the GM LS2 engine is one of their top small-block V8s to build. Out of the box it produces pretty good performance, making 400 horsepower and 400 lb-ft of torque, but with mods it really turns into a beast. You can find moderate power bumps with just headers and an intake, or you can really improve output with cams, heads, and ECU tuning.
The LS2 loves to make big power, and it is incredibly reliable to boot. You really won’t need to consider upgrading anything internally unless you plan on adding forced induction. The naturally aspirated LS2 responds very well to bolt-ons, and is a solid power plant for any build.
Let us know about your LS2 experiences in the comments below! And you can click on the link if interested in reading about other Chevrolet Mods Guide