The Pros & Cons Of 5 Cylinder Engines
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 getting up to highway speed at the end of an on-ramp. Jalopnik's own Daniel Golson used to daily a gorgeous yellow 1984 Mercedes 300TD wagon, and the lucky dog got to experience its blistering turbo-assisted 13.2-second 0-60 mph capability. That's Top Fuel dragster territory compared to the naturally-aspirated 300D, and practically teleportation compared to the 240D. Of course, now Daniel gets to drive cars like the 401-hp inline-five 2025 Audi RS3 with its trick torque-splitting differential, which is a bit quicker than a Mercedes-Benz turbodiesel from over 40 years ago.
Sadly, 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 completely phased them out, as has every other company that made a five for passenger-car use. 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, though it's not gonna stick around, either. It's a shame since Audi also has a long history with the five, as it produced the first gasoline-powered example for public consumption in 1976.
Fives are disappearing because even though they come with some notable pros, the cons are starting to outweigh them. We'll start with the cons; not because we're pessimists, but because that allows this article to end by praising the glorious five-cylinder, which powered the vivacious Volvo 850R, the atypical Acura Vigor, the common Chevrolet Colorado, the adventurous Audi Quattro, and the ferocious Ford Focus RS500.
Five-cylinder cons: They breathe weird and rock hard
Here's a neat quirk: Fives hate carburetors. The problem with them is that the central cylinder gets most of the air-fuel mixture. Plus, the standard 1-2-4-5-3 firing order means two adjacent cylinders fire right in succession not once, but twice. So, with the first cylinder still working on its intake stroke while the second is just starting, the former gets all the air and fuel while the latter gets little to none. Without five individual carburetors, a five will never run properly. Fuel injection fixed this, of course.
Rocking is another issue. There are two common firing orders with five-cylinder engines, with 1-2-4-5-3 being the predominant one. The other is 1-5-2-3-4, which introduces a massive rocking couple – the term for when cylinders on either side of the engine's center of mass fire one after the other, causing a rocking motion. There's a small rocking couple in 1-2-4-5-3 when going from cylinder two to cylinder four, but it's comparatively insignificant. The 1-5-2-3-4 firing order is often used in V10s because it minimizes secondary imbalances present in the 1-2-4-5-3 order (not that anyone makes a V10 for production cars in 2025). Plus, while inline-fives are vertically balanced, their rocking tendencies require balance shafts for smooth running, regardless of the order.
Finally, fives are longer than fours and coarser than inline sixes. Manufacturers can more easily reduce a four-cylinder's power deficit with turbocharging while giving it compact, cube-like dimensions to boot. And if you're extending engine bays for five-cylinders, why not use a six, which is inherently smoother and can yield more power? Between efficiency, packaging, and engineering challenges — not to mention a lack of market demand — most manufacturers have decided that five is either too much or too little.
Five-cylinder pros: Heavenly sound and primary balance
The first pro is underlined, bold, italicized, and in all caps because it deserves to be. Just listen to the SOUND of these fives:
Musicians among you might recognize the major third interval going parallel up the rev range. It's also quite pronounced in V10s. That soul-singer smoothness 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 power strokes don't slam down on it at 180 degrees like they do in four-cylinders.
There's also the flip side of the packaging problems mentioned earlier. With transverse mounting, inline fives thumb their noses at inline sixes. To make a six fit in the Volkswagen Corrado, the engineers at VW did the crazy VR6 "narrow-angle-V" layout, but maybe, just maybe, they could have saved some headaches by going with 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 a straight-six or a V6.
That's not to say that Volkswagen didn't try a five-cylinder. A VR5 powered New Beetles, Golfs, and Passats, with its cylinders in a narrow V-formation putting three on one side and two on the other. What's even crazier is that Honda put a genuine V5 in its MotoGP motorcycles. With a 75.5-degree vee angle and the fifth piston acting like a balance shaft, it was able to hit 20,000 rpm. And it worked beautifully, powering bikes that won 14 of 16 races in 2002.
So, pour one out for the five, friends. And let's hope that the 25th Anniversary VW Golf R with the Audi five-cylinder lets that engine go out with a bang.
