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For better or worse, the addition of forced induction has become almost obligatory when designing a modern engine. Because of this, a 2.0-liter street engine can now produce the horsepower of a 3.0-liter n/a engine and sometimes even more. But back in the day, when turbochargers were not so popular, people could get an idea of an engine’s capability solely from its displacement. Some of you might know that displacement is calculated by multiplying the bore and stroke and then multiplying that by the number of cylinders. But in some cases, the result doesn’t match the badge. Here are some of the offenders.

Ford Modular 5.0

We all know about the third-generation Mustang, also known as the Foxbody. It was said to be the beginning of the Mustang’s return to glory. And although back in the late 1970s, the oil crisis was still strangling engine performance, by 1990, as a last hurrah for the Foxbody, the 5.0 made a return. As you would expect it featured a massaged version of the 302 cubic-inch V-8, producing 235 horsepower (168 kW) and 300 pound-feet (407 Nm), allowing for a 0-60 mph (97 km/h) sprint in 5.9 seconds. But, the 5.0 wasn’t exactly a 5.0. Its 302-cubic-inch displacement equates to 4,948 cubic centimeters, which technically makes the engine a 4.9-liter. Ford, of course, knew that but decided to market it as the 5.0 in order to commemorate the 1969 BOSS 302.

Aston Martin 6.0 V-12

Six Engines That Lied About Their Displacement
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We all know and love the sound of Aston Martin’s recently retired normally-aspirated V-12 engine. It was used for a few decades in various Astons, with power ranging from 420 to 600 horsepower. The engine was actually derived from the Ford Duratec V-6 – one of the most versatile engines ever made, which can be found in anything from a Ford Mondeo to cars like Noble and Radical. The engine was initially a collaboration between Mazda and Suzuki, with input from Porsche. The Aston Martin V-12 was basically two of these engines slapped together and heavily-modified. However, don’t be fooled by the “6.0 V-12” badge on the engine cover, as the engine actually displaces 5.935 cubic-centimeters (362 cubic inches), effectively making the engine a 5.9-liter.

Mercedes AMG M156 / M159 V-8

The M156 is the first engine designed autonomously by AMG. The M156 is used in all AMG 63 models from 2006 to 2011. The M159 is a derivative of the M156, featuring a dry sump, a revised intake system, and a valvetrain. It’s used in the SLS AMG and SLS GT3 racecar. Power for the M156 ranges from 450 to 525 horsepower, depending on the application and model years, while the M159 develops from 571 to 631 horsepower. However, despite what the badges suggest, both of these German engines do not displace 6.3 liters. Their actual displacement is 6,208 cubic centimeters (379 cubic inches), which means that the actual displacement is 6.2 liters. As with other engines, the manufacturers knew that. In this case, the masters from AMG decided to commemorate an old model with the 63 badge, hence the misleading name.

Mercedes M120-E70 V-12

The Mercedes M120 was one of the go-to units in the 1990s and early 2000s if you were a start-up manufacturer focusing on exclusive hypercars. Because of this, the engine is found in cars like Pagani Zonda, as well as concepts like the Chrysler ME Four-12. Whether normally-aspirated or turbocharged, the M120 was a torque monster capable of turning tires into smoke, in record times. A version of this engine was fitted in a very limited production R129 Mercedes SL. The car in question was the Mercedes SL70 AMG, which used a version of the engine, displacing 7,055 cubic centimeters (431 cui). Although it’s a bit of a stretch, mathematically-speaking this classifies the engine as a 7.1-liter, which makes it bigger than the name suggests. The unit itself produces 496 horsepower (365 kW) and 531 pound-feet (720 Nm).

Ford BOSS 302 V-8

Six Engines That Lied About Their Displacement
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Ford makes a comeback on the list with another V-8. This one dates all the way back to 1969 when Muscle Cars were still going strong. The car was basically a road-going version of the Mustang, Ford raced in the Trans Am and Australian Touring Car series. It was a bare-bone, no-nonsense race car for the road, or at least it was advertised as one. Just like our first entry, the engine was advertised as a 5.0-liter, when it was actually displacing 4.9 liters. It did have a punch, however, as it produced 294 horsepower (216 kW) and 290 pound-feet (393 Nm). The 302 Special brought these figures up to 406 horsepower (298 kW) and 343 pound-feet (465 Nm). This allowed for a 5.2-second sprint to 60 mph (97 km/h) and a top speed of 157 mph (254 km/h).

Mercedes M113 / M113K / M155

Six Engines That Lied About Their Displacement
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Mercedes seems to have a habit of this. Another offender made by the AMG division is the M113 used in all 55 AMG versions of Mercedes-Benz cars. However, the actual displacement is 5,439 cubic centimeters (332 cui), which effectively makes this a 5.4-liter engine. Now Mercedes doesn’t hide that, but in many reviews, the engine was also referred to as a 5.5-liter and since the badge also says 55, it eventually got stuck in people’s minds. The unit produced from 347 to 367 horsepower (255 to 270 kW) and 376 to 391 pound-feet (510 to 530 Nm). The M113K was the supercharged version of the engine, most notably used in the E55 AMG as well as the CLK DTM GTR. Depending on the application, it produced 476 to 582 horsepower (350 to 428 kW) and 516 to 590 pound-feet (700 to 800 Nm). The M155 is basically the same engine but used in the SLR McLaren, where it produces up to 650 horsepower (478 kW) and 605 pound-feet (820 Nm).

Dim Angelov
Dim Angelov
Born in 1992, I come from a family of motoring enthusiasts. My passion for cars was awoken at the age of six, when I saw a Lamborghini Diablo SV in a magazine. After high school I earned a master’s degree in marketing and a Master of Arts in Media and Communications. Over the years, I’ve practiced and become skilled in precision driving and to date have test driven more than 250 cars across the globe. Over the years, I’ve picked up basic mechanical knowledge and have even taken part in the restoration of a 1964 Jaguar E-Type and an Alfa Romeo Giulia Sprint. Lately, I’ve taken a fancy to automotive photography, and while modern cars are my primary passion, I also have a love for Asian Martial Arts, swimming, war history, craft beer, historical weapons, and car restoration. In time, I plan my own classic car restoration and hope to earn my racing certificate, after which I expect to establish my own racing team.  Read full bio
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