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The GM small block V8 is one of the most well-known and successful engines ever. It started life in 1954 and went through two clear generations – the first one retroactively named Gen I, followed by Gen II. GM decided to overhaul the range and stay competitive, creating the ‘Gen III’ small block in 1997 that debuted in the C5 Chevrolet Corvette. It started a legacy that continues to this day. This was the engine in the Corvette from 1997 to 2004; the LS engine would also appear in the Camaro and Pontiac Firebird. Over time, the LS engine range increased in size dramatically with a great number of variants, ending up with the LT6 engine in the C8 Chevrolet Corvette Z06.

One unifying feature of the LS V8s is the 90-degree bank, as well as all versions of the engine have aluminum heads (except for just one – the LQ4). All are OHV pushrod engines that feature 2 valves per cylinder, and the LS family also includes just a few V6 versions with 2 cylinders removed. Today, the LS engine is one of the go-to solutions for engine swaps, even for Ford Mustangs and other non-GM brand vehicles – such is the LS engine’s cost-effectiveness and robustness. We looked at just 12 models that featured some of the better-known versions of the LS engine from Gen III to Gen V, although there were many more variants and derivatives produced.

General Motors LS V8 – Third Generation

C5 Chevrolet Corvette (LS1)

GM debuted the Gen III small block LS1 V8 in the C5 Chevy Corvette, which used an aluminum block and heads that were lighter than the iron block engines from the past. It had various improvements made to the intake and exhaust manifolds that boosted power and torque slightly. This was the engine for the base Corvette coupe and convertible from 1997-2004, while the Z06 got a tuned version of the LS1 called the LS6, which offered 385 hp. Along with the new LS1 engine, the C5 Corvette was a big improvement over the C4, with a lighter, improved platform and 50:50 weight distribution. The LS1 is also featured in the Camaro and other GM brands, such as the Pontiac Firebird/GTO, as well as the Australian brand Holden.

C5 Chevrolet Corvette Z06 (LS6)

Chevrolet introduced the LS6 for the C5 Corvette Z06 – it was based on the LS1 but with extensive modifications made to increase power and performance. A higher compression ratio was used, and the block was modified. Other changes were made to the intake manifold, valves, and oiling system, as well as a new camshaft. Its power boost from 385 hp to 405 hp occurred in 2002, and this engine continued in the Z06 model until 2004, although it also featured in the Cadillac CTS-V and the SSC Ultimate Aero American supercar. The Z06 was lighter than the standard C5 ‘Vette and featured other upgrades, including the suspension, wheels, and other areas. It was only available with a manual transmission and is easily identifiable by the rear brake cooling ducts in the rocker panels.

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General Motors LS V8 – Fourth Generation

Pontiac GTO (LS2)

While the fifth-and-last generation Pontiac GTO received the LS1 engine for 2004, in 2005 and 2006, it received the new LS2 in response to America’s desire for more power – it boosted horsepower from 350 hp to 400 hp and torque from 365 lb-ft to 400 lb-ft. This larger 6.0-liter engine would take over from the 5.7-liter LS1 for the C6 Corvette range and was now from the ‘Gen IV’ era of LS engines. The LS2 featured some changes to the blocks and location of components but was largely similar to the previous generation. It shares a lot in common with the 6-iter LS6, with changes made to improve torque. Pontiac’s GTO was in its last generation by this point, and many weren’t swayed by its understated staying, but the 2005-2006 GTO still makes for one of the cheapest ways to get hold of 400 hp in 2024.

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Pontiac Grand Prix GXP (LS4)

Appearing in the 2005-2008 Pontiac Grand Prix GXP sedan as well as the Chevy Impala, Monte Carlo, and Buick LaCrosse Super, the LS4 is interesting because it was developed as a 5.3-liter powerplant for transverse (rather than longitudinal) front-wheel drive cars, such as the Grand Prix above. With a lower output of 303 hp, the unit still shared the cylinder head design of the LS6, although it was based on the Gen IV block. The GXP was a V8-powered version of the standard V6 Grand Prix. With this much power and this much weight punishing the front wheels, torque steer and understeer were inevitable – however, Pontiac tried to mitigate this by using an interesting setup that put wider rubber on the front wheels.

C6 Chevrolet Corvette Z06 (LS7)

As well as offering the C6 Corvette with the LS2 and later the LS3 in 2008, Chevrolet also fitted the iconic sports car with the biggest LS engine to date for the Corvette Z06 – the LS7. Displacing 7 liters, this engine was a real step up from the C5 Z06’s LS6, offering far more power and torque. Based once again on the Gen IV LS engine, it had a larger bore/stroke and a dry sump oiling system, as well as a forged crankshaft, bearing caps, and connecting rods. This engine remained the most powerful naturally aspirated engine from GM until the arrival of the LT6 – the awesome powerplant for the C8 Z06. Chevrolet’s C6 Z06 was lighter than the standard model, too, thanks to the use of aluminum and composites in its construction, and featured cosmetic changes such as a front inlet scoop. The LS7 also appeared in the Corvette 427 convertible and Camaro Z-28. It wasn’t the king of the ‘Vette range, though – that was the LS9 below.

C6 Chevrolet Corvette ZR1 (LS9)

Chevrolet needed something special for the track-focused C6 ZR1 – which was the LS9. It wasn’t 9 liters, though – but it did come with a supercharger to boost power to insane levels. Based on the new 6.2-liter LS3 (which itself was an updated, larger displacement evolution of the LS2), it was ideal for the extra stress generated by the supercharger. The LS9 once again featured many upgrades to the engine aside from the Eaton roots-type charger, including lightweight, forged aluminum pistons and upgrades to the injection system. It was used only for the 2009-2013 ZR1, but Holden’s ‘HSV’ performance arm also harnessed the potential of the LS9 for its GTS sedan. The ZR1 was more than just a supercharged, one-trick pony – it came equipped from the factory with adjustable ‘Magnetic Selective Ride Control’ suspension, carbon ceramic brakes, and lighter overall weight thanks to composites in its construction such as a carbon fiber roof. Its iconic transparent hood bulge also allowed onlookers to peek at part of the engine within.

Chevrolet Camaro SS (LS3)

Chevrolet introduced the LS3 as a new, larger engine for the C6 Corvette in 2008, supplying the car with 30 hp and 24 lb-ft extra. It also featured in the 2010-2015 Camaro SS too. Only the Camaro, the manual SS model, got the LS3, while the automatic SS received a more fuel-efficient L99 derivative with a lower output of 400 hp / 410 lb-ft. The LS3 engine made the fifth-gen Camaro far more powerful than the entry-level V6 models. GM’s LS3 was an evolution of the LS2, with an altered compression ratio, as well as changes to the valvetrain, injectors, and the intake manifold. This would be followed by the Gen V LS engines, which would take performance to new heights.

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General Motors LS V8 – Fifth Generation

C7 Chevrolet Corvette Stingray (LT1)

GM’s fifth-gen small block engines are from the current generation. The new LT1 featured in the C7 Corvette base model introduced in 2014, which made 455 hp (up from 426 hp in the LS3). Despite sharing some similarities to the Gen IV LS engines, the Gen V LT1 is mostly non-interchangeable with the LS3 due to changes to the engine’s design, such as the intake/exhaust valves, cooling system, and cylinder heads, although it did share the same bore/stroke. Variable valve timing, direct injection, and other modern features are hallmarks of the Gen V range. Chevy’s updated C7 Corvette featured a radical new design that proved divisive, and once again, other performance-focused derivatives would use different engine variants, such as the LT4-powered Z06 / LT5-powered ZR1. Other cars to use the LT1 include the Camaro SS / LT1.

C7 Chevrolet Corvette ZR1 (LT5)

Chevrolet shocked the world in 2017 with its Corvette ZR1, a model that would emerge in 2019 as a final hurrah for the C7 generation and the last front-engine Corvette family. The ZR1 is a track-focused variant of the 2014-2019 Corvette that builds further on the LT4-powered C7 Z06 with a more powerful engine – offering 105 hp / 65 lb-ft more – thanks to a larger supercharger and other powertrain modifications. Of course, there were changes to the chassis for sharper handling and to the outside as well to aid in cooling/downforce. The latter included a rather aggressive aero package that added elements such as large vents, a prominent front splitter, and a large rear wing. The supercharged LT5 was limited to the ZR1 and also as a crate engine only. It is even more powerful than the C8 Corvette Z06, with far more torque, making the LT5 one of Chevrolet’s greatest hits and the most impressive iteration of the Gen III-Gen V small blocks.

C8 Chevrolet Corvette Stingray (LT2)

2020 brought the C8 Chevrolet Corvette and with it – the new LT2 engine, designed for the new Corvette’s mid-engine layout. A subtle boost in power offered up to 35 hp more than the C7 Stingray’s LT1, but the new engine was also built with a dry sump oiling system for better performance on a track. It still shares the same capacity as the similarly-naturally aspirated LT1 too and power also goes to the rear wheels. Unlike the LT1 however, the LT2 hasn’t seen action in any other GM models. Its peak power of 495 hp pushes it close to the legendary LS7 engine from the C6 Z06 that made 505 hp and similar torque. As well as being rear-mid-engine, the new Corvette also binned the manual transmission, another divisive feature of the C8.

Cadillac CT5-V Blackwing (LT4)

Cadillac’s CT5-V Blackwing received the LT4 – an engine that was also given to the C7 Chevrolet Corvette Z06. The supercharged LT4 is based on the naturally aspirated LT1 with many upgrades under the skin. These include stronger cylinder heads, lighter valves, forged pistons/connecting rods, stainless steel exhaust manifolds, and much more. This makes the LT4 30 hp / 55 lb-ft more powerful than even the C6 ZR1’s awesome supercharged LS9. In the case of the CT5-V Blackwing, the 4-door sports sedan builds on the CT5-V’s 3.0-liter, twin-turbo V6, which makes 335 hp / 405 lb-ft with an insane increase in power. It still sends power to the rear wheels and still offers a manual transmission, making it one of the few sedans still on sale with this desirable combination of features.

Honorable Mention: The LT6

C8 Chevrolet Corvette Z06 (LT6)

The C8 Corvette Z06 steals the show with the LT6 – an engine that no one was expecting in a car no one was expecting. Adding to the radical departure for the Corvette in its eighth generation, the all-new LT6 was also a milestone for naturally aspirated engines thanks to its peak of 670 hp. GM’s LT6 is now no longer part of the Gen V small block family due to a major rework of its design, one of the key features being the introduction of a flat-plane crankshaft. Flat plane cranks offer quick response, a higher rev limit, and are lighter than cross-plane crankshafts, which are more commonly featured in V engines. There was also the introduction of dual overhead camshafts for the LT6, which adds two camshafts to each bank of cylinders for a total of four, replacing the pushrod design that was part of the small block family for decades.

A Legacy That Still Isn’t Over

The C8 Corvette will reportedly get a further upgrade with a twin-turbo version of the LT6 called the LT7 for the upcoming ZR1. There could even be a future incarnation of the hybrid Corvette E-Ray called the Zora that combines the LT7 with electric motors to create the ultimate Corvette. In any case, Chevrolet’s C8 Corvette broke all the rules and reinvented an icon, but the LS and LT engines paved the way for the future of performance engines. From the C5 Corvette to future stars in the making, one humble engine range that can trace its roots back to the 50s is responsible for a great legacy that still isn’t finished.