From popular engine swaps to powering the most important American supercar, Chevy’s LS engine is a true legend and perhaps the best V8 ever made!
Many automotive experts consider Chevrolet’s LS engine as one of the best V8s of all time. Sure, it may seem like a strong statement at first glance, as there are so many alternatives to choose from — both Ford and Dodge also have a pretty decent lineup of superb V8 engines, for instance.
The competition is even fiercer if we look across the oceans to see what European and Japanese manufacturers have to offer. After all, several of these pack more punch than the LS or have introduced revolutionary new technologies. Still, from a gearhead’s point of view, these are not the only features that make an engine great. Indeed, it also needs to be widely available, affordable to tune, and, more importantly, easy to live with. Since Chevy’s LS ticks all these boxes and more, we think it might very well be the best V8 of all time.
Not sure? Let’s discuss…
What Is an LS Engine?
To understand the story and idea behind the LS engine, we have to look at its predecessor, the legendary Small Block. Chevy’s iconic all-rounder traces its roots back to the 50s and gained massive popularity in the first Corvette. Still, thanks to numerous variants and incredible reliability, the engine found its way into a wide range of GM models.
Despite slight differences, all these engines had the same basic V8 layout and used an Over-Head-Valve (OHV) technology, with the camshaft in the block and pushrods operating the valves. Thanks to this, Small Block engines were compact, reliable, and even better, quite powerful.
By the late 80s, as the Small Block was deep into its 2nd generation, features such as fuel consumption and emission controls became increasingly important. Since it was obvious that this was something a classic big V8 would never be good at, GM started working on a replacement. Like most other manufacturers at the time, the initial idea was to switch to a Dual Overhead Camshaft layout. But after initial testing, General Motors’ execs decided that such engines would not be suitable for their sports cars; the would-be new engine was simply not as smooth and responsive as its outgoing predecessor. With that in mind, GM scrapped the DOHC concept and decided to give the classic pushrod engine one more go.
The upcoming new Small Block engine had been redesigned from the ground up, as engineers only reused the shape of the block, and that’s it. These engines were made available either as LT versions, intended for trucks and SUVs, or sportier LS variants. The most notable difference between the two was the engine block, as the LS engine used aluminum instead of cast iron, making it lighter and more suitable for sports car applications.
The Differences Between LS Versions and Generations
Generation III
The first LS engine, designated as LS1, debuted in the new C5 Corvette during the late 90s. Thanks to the 5.7 liters of displacement, it churned out 345 hp and 350 pound-feet of torque in its standard version — not bad, but nothing to call your mom about either. Still, the new engine was far more efficient than its predecessor and produced lower emissions due to active fuel management and variable engine displacement. The latter meant the LS engine could shut down half of its cylinders under low loads, significantly reducing fuel consumption when cruising. Hence, it was fast when you needed it to be and kind to the environment when you didn’t — the best of both worlds.
Also worth mentioning, a higher-output version, called LS6 name, was released in 2001. Thanks to several internal upgrades, such as a revised camshaft and higher compression ratio, this engine pushed out 400 hp and the same amount of torque.
Generation IV
Chevrolet introduced the new C6 Corvette in 2004 and, with it, the next generation of LS engines. The first model, designated as LS2, had a 6.0-liter displacement, a bit bigger than the engine it replaced. Interestingly, power output remained almost the same, but the new engine now offered better torque distribution throughout the band. This version also served as a basis for the NASCAR racing engine.
With this generation, Chevy also decided to create a Small Block engine designed for transverse-mounted applications called LS4. The smaller and detuned version had a modified serpentine drive and shorter crankshaft housing, making it more compact. As such, LS4 engines could be mated to transaxle transmissions and fitted into front-wheel-drive cars.
In 2008, Chevy replaced the LS2 engine with a revised one, predictably named LS3. The displacement was once again increased, this time to 6.2 liters, and several major internal components were upgraded, including higher-flowing cylinder heads and a dual-mode exhaust system. As a result, the power output rose to 430 hp and 425 pound-feet of torque.
Still, the ultimate peak of this generation was the LS7, a true engineering masterpiece. Indeed, this hand-built 7.0-liter pearl had internals made from nothing less than materials used for racing engines, including forged titanium connecting rods and sodium-filled exhaust valves, just to name a few. The result was staggering, with the engine delivering over 500 hp and revving up to 7000 RPM. Sure enough, this was anything but an ordinary, lazy muscle car engine.
Generation V
For reasons only known to them, Chevrolet decided to change the name to LT for the latest iteration of their famous powerhouse. But despite this irregularity, the current version, released in 2014, is indisputably the most modern “LS” engine. Cutting-edge features, such as variable valve timing and direct fuel injection, made it even more responsive and ensured an additional increase in power output. The power bump wasn’t so evident on the LT1, as it was only slightly more powerful than the previous model. However, the current LT2 engine reveals its true potential, producing almost 500 hp and an astonishing 470 pound-feet of torque. And if that wasn’t enough, Chevy even came up with two supercharged versions, LT4 and LT5, pushing between 650 and 715 hp!
Which Cars Use LS Engines?
For most people, the Corvette will always be the main model associated with the LS engine. After all, these two have been inseparable since the 90s. Still, this incredible V8 engine found its way under the hood of many other GM models. For instance, the first LS1 was also available in the Chevy Camaro and Pontiac GTO. Cadillac also used the more powerful LS6 version in its CTS-V, blitzing the Nurburgring and proving itself to be much more than a pensioners’ car.
With Generation IV engines, the application range was even more diverse. Apart from the Corvette C6, these were used in the sporty Chevrolet Trailblazer or front-wheel-drive cruisers, such as the Chevrolet Monte Carlo.
Unlike its predecessors, all naturally-aspirated Generation V engines are solely reserved for the most sporty applications. The first LT1 was available in Corvette C7 and the most powerful Camaro SS, the current LT2 engine is only available in the brand-new, mid-engined Corvette C8, and supercharged variants are fitted in the Cadillac CTS-V and Escalade.
Are LS Engines Reliable?
Since the LS engines’ design results form decades of evolution, with most teetering problems being solved ages ago, they are now incredibly robust. The push rod configuration, which eliminates the need for a complex timing drive, is another significant advantage. Sure, the LS engine still has a timing chain, but the simpler assembly usually outlives the vehicle itself and rarely needs any attention.
There are, however, some potential downsides to consider, including porous heads that may crack on the early LS1 engines. In addition, many will argue that the power output is not that spectacular, considering the given capacity.
But, of course, this is where tuning and the availability of a wide range of aftermarket and performance components come into play.
How Much Tuning Potential Do LS Engines Have?
While some may claim the LS is an underpowered engine, others appreciate its hidden tuning potential. Indeed, due to the production spanning such a long period and its popularity in the tuning community, the aftermarket industry is now full of performance components for the LS, including bolt-on parts instantaneously increase power and torque.
For instance, it’s possible to achieve significant gains only by fitting custom headers with high-flow catalytic converters and a custom tune. More aggressive camshafts are another popular option, as they increase power output at a specific rev range. And if you really want to go big, there is also a range of application-built superchargers and nitro-systems to choose from. In some cases, with the right components and a sufficient budget, it is even possible to double the power output.
However, this observation brings another question. If it’s that easy to pull extra ponies out of an LS engine, why did GM build an engine delivering less power than it is actually capable of? The answer is in the balance of different requirements, which all manufacturers have to make when designing their vehicles. The power is only one side of the story, as road-going engines must also be durable and comply with various emission regulations. Other aspects for designers to consider are the running conditions, which can be unfavorable in many cases. Additionally, many upgrades will create a peak in power output at a narrow rev range while causing a noticeable drop in others, affecting the engine’s performance at low speeds.
After all, unless they are building a track-focused supercar, they need to take into account that owners will also use their car to go to work, bring the kids to soccer practice, and only very occasionally, put the pedal to the metal.
Why Is LS-Swapping So Popular?
As an engineering masterpiece with so many upsides and only a few downsides, LS engines quickly became more popular than the vehicles they originally came in. The compact dimensions make them excellent for smaller engine bays, where most of its competitors would not fit that easily. In addition, the less complex architecture with fewer electronics made installing aftermarket stand-alone ECUs much easier. Lastly, achieving noticeable gains is fairly easy, thanks to the robust construction and widely available bolt-on performance upgrades.
The LS engine is and has been, for some time, the favorite and one of the most common choices for many custom-made project cars. As a result, it is easy to find all sorts of non-GM vehicles where their owners replaced the stock engine with an LS, including anything from Japanese sports cars to classic muscle cars and plain-looking sleepers.
The trend is now so widespread that it is even known under the “LS swap” name, with its own hashtags and other social media acronyms. Heck, it even has its own Wikipedia page! These unusual vehicles show what is possible to achieve with some effort and imagination.
One thing led to another, and the demand only ever increased; GM had no other choice but to start selling them as crate motors. For example, the LS3 was even available at Walmart as a long block unit with all the electrics and accessories!
Verdict
Now, no matter whether you think GM’s LS V8 is the best of its kind or not, it’s easy to see why so many think so. For starters, it is a very reliable engine, thanks to its time-proven design and robust construction. Secondly, the range of cutting-edge innovations now makes it quite fuel-efficient and environmentally friendly (ok, it might not be so fuel-efficient if you slap a supercharger on it, but you know…).
Lastly, these engines have the potential to produce impressive numbers, with an incredible range of aftermarket performance parts available — and because of the size of the LS community, there is no shortage of knowledge out there. No matter the kind of car you want to fit an LS on, somebody did it before and is probably ready to help by sharing his experience.
So ok, but what about Chrysler’s 426 Hemi, Ford’s 302, Mercedes’ Hot-V, Ferrari’s F106, and all those other legendary V8, then? True, you might very well have a point here — but we’ll have to keep this for another article.
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