The pros and cons of 5-cylinder engines – Jalopnik

Having lived with a four-cylinder Mercedes 240D and a five-cylinder 300D, I can tell you that the extra cylinder makes a huge difference in gaining highway speed at the end of an on-ramp. Jalopnik’s own Daniel Golson drove a beautiful yellow 1984 Mercedes 300TD wagon daily, and the lucky dog ​​got to experience its blistering turbo-assisted 13.2 second 0-60 mph time. That’s Top Fuel dragster territory compared to the naturally aspirated 300D, and practically teleportation compared to the 240D. Of course, Daniel now gets to drive cars like the 401-horsepower inline-five 2025 Audi RS3 with its trick torque-splitting differential, which is slightly faster than a Mercedes-Benz turbo-diesel from more than 40 years ago.

Unfortunately, five-cylinder engines are currently on the endangered species list. Even Mercedes, the company that introduced the world to five-cylinder engines in 1974, has phased them out completely, as has every other company that introduced five-cylinder engines for use in passenger cars. That includes Volvo, Fiat, Honda/Acura and General Motors. Well, to be fair, Audi is still putting its turbo inline-five in the aforementioned RS3, although it won’t stick around either. It’s a shame, as Audi also has a long history with the five, having produced the first petrol-powered example for public consumption in 1976.

Fives are disappearing because, although they bring some notable advantages, the disadvantages are starting to mount. We’ll start with the disadvantages; not because we’re pessimists, but because this article could end up praising the glorious five-cylinder that powered the lively Volvo 850R, the atypical Acura Vigor, the regular Chevrolet Colorado, the adventurous Audi Quattro and the ferocious Ford Focus RS500.

Swinging is another problem. There are two common firing commands on five-cylinder engines, with 1-2-4-5-3 being the predominant one. The other is 1-5-2-3-4, which introduces massive rocking torque – the term for when cylinders on either side of the engine’s center of mass fire one after the other, creating a rocking motion. There is a small swing in 1-2-4-5-3 as you go from cylinder two to cylinder four, but it is relatively insignificant. The 1-5-2-3-4 firing order is often used in V10s because it minimizes secondary imbalances in the 1-2-4-5-3 order (not that anyone is making a V10 for production cars in 2025). And although inline-fives are vertically balanced, their rocking tendencies require balance shafts for smooth operation regardless of order.

Finally, fives are longer than fours and coarser than inline sixes. Manufacturers can more easily reduce the power deficit of a four-cylinder by turbocharging while giving it compact, cube-like dimensions. And if you’re expanding the engine bays for five-cylinders, why not use a six-cylinder, which is inherently smoother and can make more power? Given the challenges of efficiency, packaging and engineering – not to mention a lack of market demand – most manufacturers have concluded that five is either too much or too little.

Musicians among you may recognize the major third interval that runs parallel in the rpm range. It’s also quite pronounced in V10s. The soul singer’s softness isn’t just auditory either; it’s also in the power delivery. The 144-degree firing interval makes the crankshaft look like a star from the end, but more importantly it means the power strokes don’t land on it at a 180-degree angle like they do on four-cylinders.

There is also the downside of the packaging issues mentioned earlier. When mounted crosswise, inline fives thumb their noses at inline sixes. To get a six in the Volkswagen Corrado, the engineers at VW created the crazy VR6 “narrow-angle-V” layout, but perhaps they could have saved some headaches by going for a five. Transverse fives give you better smoothness and power potential than a four, along with better packaging with less weight than a six – whether that’s an inline six or a V6.

That doesn’t mean that Volkswagen hasn’t tried a five-cylinder. A VR5 powered New Beetles, Golfs and Passats, with cylinders in a narrow V formation, three on one side and two on the other. What’s even crazier is that Honda has put a real V5 in its MotoGP engines. With a V-angle of 75.5 degrees and the fifth piston acting as a balance shaft, it could reach 20,000 rpm. And it worked beautifully, powering engines that won 14 of 16 races in 2002.

So pour one out for the five, friends. And now let’s hope that the 25th Anniversary VW Golf R with the Audi five-cylinder engine will let that engine go out with a bang.