An engine lasted 61 years, which almost covers the life cycle of the internal combustion engine. Not to mention the evolution history of the engine, its long life alone can be called a sentimental machine. What’s even more amazing is that , it is not something that ordinary people can own, and it is difficult to find even in Chentian, because it originated from Rolls-Royce and was the core power of Bentley Mulsanne until it was discontinued. Unfortunately, this engine that has been in production for more than half a century will also be announced to be discontinued. . ?

Back in the 1950s, Bentley and Rolls-Royce were still British brands, and they were undoubtedly proud of them. During this period, this L-type engine never Major replacements are just improvements and additions of advanced technology over time. This shows the level of British manufacturing in the last century. And now if you open the engine cover of the Mulsanne, you will still see the honorary number of 6.75. ?

The birth of the V-shaped structure?

Today it is still a machine for wealthy families. In fact, it was also a product of technological innovation at the beginning of its birth. At that time, cars were the stuff of the rich, and multiple cylinders and large displacements were standard features. However, this also resulted in an oversized engine compartment and pitifully small cockpit, which almost took up the entire size of the entire vehicle. ?

Although the old rich don’t mind too much, who doesn’t want the cabin to be larger and more comfortable, so engineers came up with the idea of ??changing the inline engine to a V-shaped design. The two rows of cylinders form an angle, and the rigidity and vibration problems are solved by shortening the crankshaft. The weight, volume, and longitudinal dimensions are hundreds of times better than those of the inline. With the same vehicle length, the rich man's personal space is instantly expanded. ?

Different from the big V8s in the United States, machines made in the UK should have a gentlemanly temperament. They should not only be durable and powerful, but also smooth, quiet, calm and elegant. You can admire the machine when you open the cover. The sense of exquisiteness and artistry brought by the layout, and the foundation laid decades ago, have created brilliance that spans more than half a century. No wonder today's F1 manufacturers have their R&D departments near the UK, where the talent passed down from generation to generation is unparalleled. ?

The birth of the L410?

In 1959, the L series engine exclusively developed by Rolls-Royce and Bentley was born. Its performance in all aspects was superior to that of the same period of time. , and more importantly, not only was it powerful and low-torque, they had already optimized the engine's NVH quietness in that era, and the Lexus LS400 was still a successor. ?

We know that the current Mulsanne is labeled with 6.75L, while the earliest mass-produced L series, the L410, has a displacement of 6.25L, a naturally aspirated large V8 with an overhead camshaft and a mid-mounted Cams and wedge-shaped piston crowns were all advanced technologies that optimized the combustible mixture back then, and some of them are even still retained today. ?

The first L-series machines were used by Rolls-Royce Phantom and Bentley S-series. However, L410 was not always used. Later, L410l and L410B were launched, both of which were powered and improved on the original basis. The adjustment of torque allows this giant thing to exert great power and have more stable power. In 1968, after the second adjustment of the L-type engine, the number 6.75 actually appeared. ?

About 2014, the Rolls-Royce Wraith was preparing to enter China. I had tested it overseas. It was also my first time driving a Rolls-Royce. I was dumbfounded when I saw the dashboard. , the English word on the far left says POWER? RESERVE, instead of the traditional tachometer, expressing how much power the car still has for you, which is what we call reserve power, and the 1968 facelift was to improve it. Engine reserve power. ?

Before the birth of 6.75, the L425 machine was launched. First of all, it should be noted that 410 and 425 represent the cylinder bore, the former is 4.1 inches, and the latter is 4.25 inches. The improvement from L410 to L425 is achieved by expanding the bore, and the V8 displacement is also increased from 6.25L to 7.45L, but this does not Not what Rolls-Royce or Bentley want.

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The research and development of the L425 made them take a detour. They found that cylinder expansion could not make the L-shaped machine more stable, so they changed the stroke of the engine, increasing it from 3.6 inches in the L410 to 3.9 inches in displacement. It has also become 6.75 liters today, and the engine torque has been greatly improved. For such a heavy luxury car, torque is everything, and the backup power is even more king. ?

1998 was a watershed for Rolls-Royce and Bentley. Before, they were both fans of L-type engines. After that, Rolls-Royce was completely insulated from L-type engines. That year was the year when Rolls-Royce and Bentley separated. Volkswagen acquired Bentley and BMW acquired Rolls-Royce. However, BMW only obtained the right to use the trademark of Rolls-Royce, while Volkswagen took over the British car. A proud engine. ?

The L engine under Volkswagen?

After decades, 6.75 and Bentley are almost tied together as gold paint signs, and they continue to be used and improved even if the public accepts them. In 2006, Volkswagen added twin turbochargers to the L-type machine, which has 530hp and a peak torque of more than 1,000. Not only are the data exaggerated, but the emissions are also 99% lower than the original L410. ?

If you are a technology geek, you will probably like the increasingly stringent automobile emission regulations. Under the requirements of the law, many advanced technologies have been spawned, such as hybrid, variable cylinder and even variable compression ratio. But if you are a sentimental person, your attitude is completely opposite. Bentley announced that the reason for the end of the life of the L-type machine was emissions, indirectly announcing that large-displacement machines had been eliminated, ending its 61-year historical mission. ?

Whether it is for sentimental reasons or to make the last profit, Bentley continues to launch the commemorative edition of Mulsanne 6.75 Edition By Mulliner, with 6.75 labels on the body and engine compartment. Then he It will truly rely on Volkswagen. The cabin will be equipped with 6.0L? W12, 4.0L? V8 hybrid and 3.0L? V6 hybrid. Eventually, it will gradually move towards the Volkswagen Group's EV system. ?

This is probably the past, present and future of the L-type engine.

This article comes from the author of Autohome Chejiahao and does not represent the views and positions of Autohome.