The Chevy LS2 Engine Guide. The LS2 engine debuted in 2005, kicking off the fourth generation of Chevrolet’s small-block engine line. The Chevy LS2 is a 6.0 liter V8 engine that was manufactured until 2009. Despite having a relatively short run, it is still regarded as one of the best Chevy small-block engines of all time. It was installed in the 2005-2007 Corvette, as well as the SSR and Trailblazer SS. It immediately gained a reputation for being an extremely strong and tough machine, and it’s still extensively utilized in drag racing builds today.
This book will teach you all there is to know about the Chevy LS2 engine. We’ll look over the LS2 specifications, vehicle applications, history, engine design, several versions, reliability, and prospective upgrade options. This is the place to go for any and all LS2 information.
History of the Chevy LS2 Engine
The LS2 engine’s development began almost a decade before its sale, with the introduction of the LS1 small-block V8 in 1997. The LS1 was the first engine released as part of General Motors’ third series of small-block V8s. From 1997 through 2004, Chevy used the LS1 in the C5 Corvette, producing 350 horsepower and 365 lb-ft of torque. The LS1 engine was also used in the Camaro Z28 and SS, as well as the Pontiac GTO, Firebird, and TransAm.
The third generation of GM small-block engines marked a substantial divergence from the first and second generations, which were almost identical. Because the LS1 was the first engine in the family, the Gen III+ engines are known as the LS-series. The engines are sometimes referred to as the Vortec series. The terms LS and Vortecs are interchangeable, with the LS referring to aluminum block automobile engines and the Vortecs referring to cast-iron block truck engines.
Following the end of the domestic run of the LS1 engine in 2004, General Motors introduced the LS2 engine in 2005. LS2 was built on the LS1 as well as its high-performance counterpart, the LS6. And LS2 engine was upgraded to 400 horsepower and 400 pound-feet of torque in the Corvette. The LS2 was also used in the ill-fated SSR, Trailblazer SS, Pontiac GTO, and Cadillac CTS-V.
The LS2 was only available until 2009, when it was phased out by General Motors. It was, however, available as a crate engine for many years and is still utilized by independent builders and shops. Furthermore, a few LS2 variants lasted a few years longer, such as the L77, which lasted until 2017. While most people prefer its successors, the LS3 and LS7, the LS2 is still a reliable engine.
The LS2 Subtypes
Along with the LS2, GM released three variants: the L76, L77, and L98. These were designed similarly to the LS2, but with improvements such as Variable Valve Timing, flex-fuel compatibility, and/or Active Fuel Management – depending on the engine. These lasted until the L77’s 2017 production year, and were primarily designed for use in the Australian market by GM’s former subsidiary Holden, though some have also been used in the United States.
Chevy LS2 Engine Specifications
Vehicles that use the Chevrolet LS2 engine
Vehicle Applications for LS2
- 2005–2007 Corvette, Chevrolet
- SSR Chevrolet 2005-2006
- HSV Clubsport R8 2005-2008
- HSV Coupé GTO from 2005 until 2006.
- HSV GTS from 2005 until 2008.
- From 2005 until 2008, HSV Grange
- HSV Maloo R8 from 2005 to 2008.
- Senator HSV Signature 2005-2008
- 2005-2006 HSV SV6000
- GTO 2005-2006 Pontiac
- 2005–2006 Vauxhall Monaro VXR (Vauxhall Monaro VXR)
- Cadillac CTS-V 2006-2007
- 2006–2009 Chevrolet TrailBlazer SS
- Saab 9-7X Aero 2008-2009
L76
- Holden Commodore 2006-2010
- Chevrolet Avalanche 2007-2013
- Chevrolet Silverado 1500 (2007-2009)
- Chevrolet Suburban 1500 2007-2009
- GMC Sierra 1500 2007-2009
- Yukon XL 2007-2009 GMC
- G8 GT Pontiac 2007-2009
- Holden VE Ute (automatic only) 2008-2010
- Holden WM Statesman/Caprice 2008-2010
- Ginetta Akula 2020
L77
- Holden Caprice 2010-2017
- Holden Commodore SS 2010-2017
- Holden Sportwagon SS 2010-2017
- Holden Ute SS models from 2010 to 2017.
- Chevrolet Caprice PPV 2011-2017
L98
- From 2006 through 2009, Holden Calais
- Holden Commodore 2006-2010
- Holden Statesman/Caprice 2006-2009
- From 2006 through 2010, Holden Ute
Chevy LS2 Engine Concept
LS2 Similarities and Dissimilarities to the LS1
The Gen IV small-block LS2 from General Motors or Chevy is based on its Gen III small-block predecessor, the LS1. It has a pushrod OHV, two valves per cylinder design with an aluminum block and head. The LS2 engine features a higher compression ratio of 10.9:1, a higher lift cam, 15% better intake flow, and 20% better exhaust flow than the LS1. Power increased from 350 to 400 horsepower, and torque increased from 365 to 400 pound-feet (in the Corvette).
The bore and stroke of the LS2 were also bored out to 4.00′′ from 3.898′′ for a bore and stroke of 4.000′′ 3.622′′. This results in a total displacement of 6.0 L, up from 5.7 L in the LS1. The LS2 retains the LS1’s six-bolt main caps, 4.40″ center bore, and deep-skirt casing. Both had steel crankshafts and sequential multi-port fuel injection, with 34 lb/hr injectors on the LS2.
The LS2 aluminum block weighs 15 lbs lighter than the LS1 block in Corvettes. The lighter weight is due to a thinner-walled exhaust manifold, a smaller water pump, and a smaller oil pan. It may appear that the oil pan requires a full quart less oil than the LS1, but this is not the case. The pan’s baffles have been totally modified to maintain oil flowing through the pickup, and it is wingless rather than “gull-wing” in style. Once again, this redesigned oil pan was only for the LS2 Corvette.
The LS1’s coil-near-plug ignition mechanism was redesigned. From 2005-2006 it had a 24 tooth reluctor-wheel setup, but that was upgraded to 58-tooth system in 2007. Taken from the LS6 for the LS2 was the PCV system.
Sensor Relocation, LS2 Cylinder Heads, and Throttle Body
The LS2 cylinder head, like the LS1 and LS6, is made of aluminum and features cathedral ports. Like the LS6, the valves are steel and measure 2.00′′ for the intake and 1.55′′ for the exhaust. A 90 mm throttle body is controlled by a drive-by-wire electronic throttle control on the LS2. Although the exhaust manifold walls are 1mm (30%) thinner than on the LS1, it weighs less and flows 4% better.
To allow for more precise readings, the LS2 knock sensors are located outside of the cylinder banks. GM also relocated the cam sensors from behind the intake to the front timing cover. To eliminate piston slap, the new pistons, which are still made of hypereutectic cast aluminum, have full-floating wrist pins.
Some models, such as the Corvette, are equipped with transmissions that use Computer Aided Gear Shifting (CAGS). Because CAGS requires shifting from 1-4 at lower RPM, Chevy was able to avoid the gas-guzzler tax on most LS2 equipped vehicles. The LS2 also has a redline that is 500 RPM higher than the LS1, at 6,500 RPM.
L76 Vortec LS2 Variants
The LS2 engine is available in numerous configurations, including the L76/77/98. Chevy marketed these as VortecMax engines, and they are quite comparable to the LS2 upon which they are built. The introduction of Active Fuel Management (AFM) distinguishes the LS2 from the L76. AFM, also known as displacement on demand fueling, is a feature that shuts half of the engine’s cylinders at low loads in order to improve fuel economy and lower emissions.
Many enthusiasts are opposed to AFM because it necessitates a lower design camshaft, which reduces performance. Variable Valve Timing (VVT) for the camshaft was also added to the L76 over the LS2. VVT engines allowed for better fuel efficiency and power tuning than non-VVT engines. This mitigated the disadvantages of the lower profile cam, but the L76 was still underpowered when compared to the LS2. The L76 intake manifold was derived from the LS3 in Corvettes, and it features smoother flowing rectangular ports rather than the cathedral type head.
There are several differences between the truck and car L76 engines. Much of this was due to the engine size, as larger truck bays could better accommodate it. To accommodate the narrower bay, the automobiles had lower-rise intake manifolds, intakes, and exhaust manifolds. L76 vehicles have a compression ratio of 10.4:1, whereas trucks have a lower ratio of 9.7:1. The same fuel injection system from the LS2 was retained, but with different injector sizes: 42 lb/hr @ 58 psi for cars and 30 lb/hr @ 58 psi for trucks.
The L76 lasted in production until 2010, and Chevy put it in their Suburbans, Avalanches, and Silverados. Chevy rated the L76 for cars at 355 horsepower and 384 pound-feet of torque, and for trucks at 367 horsepower and 375 pound-feet of torque.
The L77/98 Vortecs
The L77 is basically a flex-fuel version of the L76 that can run ethanol blends in addition to petrol. Aside from that, the engines, as well as the L96 iron-block version, are eerily similar. It has AFM as well, but no VVT. The L77 was primarily used for the Australian market by former GM subsidiary Holden, but it was also used in the Chevrolet Caprice PPV.
The L98 is extremely similar to the L76 and L77, however it lacks AFM and does not support flex-fuel. Both the L77 and L98 employ the L76 intake and exhaust manifolds, as well as PCV and oiling systems. The most powerful variants of the L77 and L98 have 362 horsepower and 391 lb-ft of torque, which is significantly more than the L76.
If the L76 is an LS2 without the AFM and the L98 is a L76 with the AFM removed, is the L98 just an LS2? The answer is, sort of. They are essentially the same engine.The biggest distinctions are still the L98’s rectangular port heads and lower camshaft design – though that’s more aggressive than the L76. Some people actually argue the L98 will perform better than the LS2 – with similar cam profiles – due to the higher flowing rectangular port heads.
Common Chevy LS2 Engine Issues and Reliability
If there is one thing you can say about the Chevy LS2 engine, it’s that it is reliable. The entire LS-series is pretty much bulletproof in any respect, and there are really no big faults with them. If properly cared for and maintained, the LS2 will easily exceed 200,000 miles. At the 100,000 mile mark, these things are really just getting broken in.
Now, with that being said, there are a few things that some LS2 owners have had issues with. While we definitely would not call them common or likely issues, these have popped up for more than a few LS2 owners. Oil starvation, rocker arm bearing failure, and harmonic balancer failure are the main issues.
The oil hunger issue was mostly relevant to early LS2 builds from 2005-2006. Some early C6 Corvette owners complained about oil starvation issues resulting in thrown rods. It’s unclear what caused these, but it appears to have been a minor issue, as the Corvette quickly moved on to the LS3.
Another common complaint regarding the LS2 is rocker arm bearing failure. As we mentioned, the LS2 employs a pretty old-school and simple OHV pushrod configuration. Pushrods are synonymous with rocker arms, and the LS2’s rocker arms are notorious for premature wear and failure. Stronger bearings usually solve the problem permanently.
The final issue on the LS2 will be Harmonic Balancer failure. Harmonic balancers aid in the reduction of excessive crankshaft vibration. The LS2 harmonic balancers have received several complaints for premature failure for unknown reasons. The best way to solve the problem is to use an upgraded harmonic balancer kit.
Power Limits of the Chevy LS2 Engine
When we stated the LS2 was bulletproof, we didn’t just mean it would endure a long time; we also meant it could take power. While most builds leave the LS2 naturally aspirated, you’ll still have some leeway if you go with forced induction. The LS2 is widely thought to have stronger internals than the LS1, which is already quite robust.
The LS2 is capable of producing more than 800 horsepower on the stock block with no problems. Many stock LS2 blocks have been pushed into the 900+ whp territory without issue, but we think that’s a little risky.
After 550 wheel horsepower, you should consider forged pistons and rods, as well as head studs. Again, unlike the LS2 block, there is no hard limit, with many stock LS2 builds pushing well into the 600 and 700 whp range. If you’re pushing past 550 whp, you’ll need stronger pistons and rods for reliability.
Performance and Modifications for the Chevy LS2 Engine
Now for the exciting part: Chevy LS2 engine performance and potential mod paths. The LS2 is a very capable motor right out of the box. The 2005 Corvette can accelerate from zero to 60 mph in just 4.3 seconds. It can run the quarter mile in 12.7 seconds at 113 mph, which is quite good for an early 2000s small-block natural aspiration engine.
However, if you’re still looking to upgrade, there are numerous options. Intake, cylinder heads, long-tube headers, camshaft, and tune are the most popular LS2 upgrades. The adaptability of numerous engine parts is one of the best features of the LS-series engines. Furthermore, the LS2 long cylinder sleeves make it ideal for swaps and stroker kits. The LS-series engines are well-known for their versatility to be swapped into most engine bays, and the LS2 is no exception.
The Top 5 LS2 Modifications
While the best intake will depend on your specific model, we typically recommend a cold air intake as one of the first mods you do. One of the most important considerations you’ll have to make is whether to use closed or open airboxes. Open airboxes are more prone to heat soak in general, but they allow for better ventilation. Closed airboxes reduce airflow, but they also reduce engine heat absorption for a longer period of time. We recommend the Chevrolet Corvette C6 Vararam LS2 Intake for upgrading the intake on LS2 powered Corvettes. If you want to upgrade your LS2-powered GTO, we recommend the Pontiac GTO Cold AIr Inductions LS2 Intake.
The cylinder head is the most important thing to upgrade on the LS2 after the intake. As previously stated, the cathedral port design on the LS2 is far inferior to the rectangular port head design. An easy mod is to install an LS3 cylinder head with rectangular ports, which significantly improves flow. It is a direct fit for the LS2 and requires no modifications.
We recommend the Livernois Motorsports LS3 Stage 2 Cylinder Head as an aftermarket upgrade. The LS3 rectangular port Livernois head is CNC machined and 100% made in America. The Livernois Stage 2 Head is the way to go if you want to make a lot of power.
Following the intake manifold and cylinder head, your next mod will be to upgrade the exhaust. Long-tube headers really wake up the LS2, adding tons of power all over the place. While exhausts will vary depending on your vehicle, we recommend the American Racing Headers long-tube C6 Corvette headers. These headers provide the best of both worlds, with guaranteed performance and dependability. They are made of 304 stainless steel and can be ordered with or without cats.
Related : The Honda B20 Engine Manual
Tuning with LS2 Cams
After the intake, headers, and cylinder head, we will recommend the camshaft. Unfortunately, because the LS2 lacks VVT, the cam benefits will be less significant than in other LS-series engines. Still, it’s a decent power adder for the LS2 and well worth the money.
The Livernois Motorsports Stage 3 LS-series Cams are our recommendation. With a duration of [email protected] and a lift of 0.612 in, these are clearly designed to add some serious power.
ECU tuning will be our final LS2 engine improvement. If you plan on installing any of the above mods, you’ll need tuning to make the most of them. Your tuner can increase parameters such as ignition timing and air-to-fuel ratios with ECU tuning to make more power. If you intend to increase airflow and fueling, you should definitely compensate with the ECU.
Without tuning, you could be throwing away up to 20% of your power. Furthermore, tuning helps to keep your engine safe with the mods you’ve installed. Nobody wants to take their LS2 to the drag strip just to have it crash and melt a piston. If you’re serious about your LS2 build, you’ll want to find a reputable local tuner and get your car/truck tested on a dyno.
Legacy of the Chevy LS2 Engine
The Chevy LS2 is one of the best small-block engines ever built by GM. It is extremely dependable, has excellent performance, and is ready for upgrades and modifications. Whether you have an early 2000s Corvette, GTO, or CTS-V, or you’re considering an LS2 swap, Chevy’s 6.0 L engine will serve you well.
Today, we took a close look at the LS2, including its history, specifications, vehicle applications, design, variants, reliability, and top customizations. While we couldn’t include everything about the LS2, we did include everything you need to know before embarking on an LS2 adventure.
