What is a car without an engine? It’s undeniable that engines are the beating hearts of our vehicles. Over the years, some engines have even become “darlings” in the commercial world, as well as favorites among car and engine enthusiasts. However, no matter how powerful or efficient, some engines just don’t make the cut when it comes to rising emissions standards, ever-changing demands for fuel economy, and constant technological advancements. So what engines became a part of our history? Hop in a time machine and take a look at which designs weren’t able to stand the test of time.

10 VW Air-Cooled Engine

VW Air-cooled engines had a long run, from 1935-2005. This engine, considered one of the most reliable of any era, was discontinued in 2005 due to anti-pollution laws. Various types of this dependable engine were produced by Volkswagen for different purposes: Type 1 pictured above ran inside the Volkswagen Type 1 Beetle, Type 2 inside transporters reminiscent of The Mystery Machine, and so on.

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Some of these engines were even used in light aircraft and several industrial applications. Despite its longevity, the air-cooled engine couldn’t survive stricter emissions standards and was eventually replaced by the Wasserboxer: water-cooled engines.

9 Volkswagen Wasserboxer

Wasser meaning ‘water,’ and boxer another term for ‘horizontally opposed,’ the Volkswagen water-cooled engine was the direct answer to the call for tighter emissions standards in 1982. This engine was unique for many reasons, two in particular: it’s heron type combustion chambers, which allowed the combustion to take place in the piston rather than in the cylinder blockhead, and the fact that this engine exclusively ran inside the Volkswagen T3, or Vanagon models. A true innovation though it was, the Wasserboxer’s unique design was a recipe for disaster, and it’s continuous failures caused it to be discontinued in 1992.

8 BMW S85

The first and only V10 engine, the S85 was created to replace the S62 V8 engine in 2005. With dual-overhead camshafts, a double VANOS (variable valve timing) system and a peak of 500 hp (373 kW), the V10 was a very powerful and high revving engine. It was much beloved by petrolheads everywhere and won numerous engine of the year awards. So why was it discontinued in 2010? There are differing opinions, the most common being it was dropped in favor of BMW’s more powerful twin-turbo V8. Whatever the case, since its discontinuation in 2010, it has been sorely missed.

7 Alfa Romeo Busso V6

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The iconic Busso V6, named after its “father” Giuseppe Busso, was renowned for having the best sound of all the engines in the six-cylinder lineup. Produced in 1979, the Busso was naturally aspirated and ranged from 2-3.2-liters in displacement. It also saw many alterations during its production life.

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The 164 engine had a DOHC, aluminum-alloy engine block and sodium-filled exhaust valves. The 147 model could put out 300 hp and do 0-62 in under 6 seconds. Sadly, this musical engine was discontinued in 2005. Sadly, its creator died a few days after the last engine was produced. The end of an era.

6 Toyota JZ-GTE

The JZ Inline 6 engine was a powerhouse from Japan. This engine was produced in 1990 and had two generations, but the 2JZ is what took the industry by storm. Outfitted with parallel turbochargers and an over 500-pound cast-iron cylinder block, the 2JZ reached 320 hp and could do 60 mph in 5 seconds. Due to its tough as nails build, it became popular in the tune-up scene as gearheads and drag racers everywhere found ways to make it even more powerful. However, the JZ proved to be too costly to produce and maintain, so it was discontinued in 2007.

5 Volvo Mod 5 Cylinder

For a time, Volvo’s 5-cylinder engine was considered a perfect compromise between 4-cylinder and 6-cylinder models. In 1991 they released the 850, an inline 5-cylinder engine, one of many identical engines that made manufacturing cost-effective.

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The Mod 5 was compact and fit into tighter spaces than a 6 cylinder, but provided more power and a smoother ride than 4 cylinders. It seemed perfect, until the industry upped its game on 4-cylinder production, making them more powerful and efficient. Eventually, the 5 cylinder became redundant and was discontinued in 2014, and a comeback doesn’t look likely.

4 Ford Barra I6

Produced from 2002-2016, the Ford Barra (short for “Barramundi”) was exclusively manufactured in and loved by Australia. The Barras were known for their high torque rather than power, torquing ability outweighing rpm by a significantly large margin. The Inline 6 style boasted a smooth, balanced force with no need for counterweights or balancing agents because of its mirrored pistons.

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It was also a great base for tuneups, strong enough to take the brunt of suped-up turbochargers. Ford pulled production in late 2016, alongside the Australian Ford Falcon. Despite the discontinuation, for tuners, The Barra is still just as desirable.

3 Nissan RB Series

The RB series was never sold in the states, but several models are still legendary among car enthusiasts, especially tuners. Although Nissan manufactured many powerful models with DOHC, electronic fuel injection, and turbochargers, the most memorable got its life in the aftermarket: the RB30DET. Modifying the already powerful RB25DET, tuners brought the RB30DET into being. Sounding like something out of the industrial revolution, this engine is not the easiest to listen to, but it packs a punch on the Australian/New Zealand drag scene. Pulled from production in 2004, the RB series will be making a comeback this year.

2 Mazda Rotary Engine

Since 1967, Mazda and the rotary engine went hand in hand in the minds of the public. Also known as a ‘Wankel’ engine, the rotary, due to its lightweight and compact make was highly favored by kit car builders, tuners, hotrodders, and even aircraft enthusiasts. With its high power-to-weight ratio, gearheads saw and capitalized on its tuning potential. However, although small and powerful and admittedly versatile, the rotary engine had a reputation for poor fuel efficiency and was decommissioned in 2012. According to Mazda, the rotary engine will be returning to cars in 2019, but apparently, in an electric model.

1 Volkswagen VR6

While some engines are returning, it seems one engine is on its way out. The VR6 engine has certainly had its heyday; when it first appeared on the scene in the 1990s it revolutionized the industry. While reliable, this engine was designed before turbo technology improved 4-cylinder performance. With inline 4-cylinder models offering more power and more efficiency in a smaller, more compact package, 6-cylinder models can’t offer much more by way of reliability and torque. In fact, the VR6 has been discontinued altogether in Europe. While the 6-cylinder engine is not yet discontinued here, it very soon might be.

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