- 3-Cylinder Cars: The Basics
- Pros of 3-Cylinder Engines
- Cons of 3-Cylinder Engines
- Rumors About 3-Cylinder Engines
- 3-Cylinder Cars
- MINI Cooper Hardtop
- BMW i8
- Toyota GR Corolla
- Koenigsegg Gemera
- 3-Cylinder Cars Still Sold In America
- Forbidden 3-Cylinder Fruit
- Ford Fiesta ST
- Toyota GR Yaris
Three-cylinder cars aren't just about getting good fuel economy, anymore, they now power everything from compact sports cars to high-end hypercars.
As enthusiasts, we've been psychologically trained to believe that bigger is better. Often, we associate sports cars with large gas-guzzling V8s, and supercars are expected to house screaming V10s or V12s. Some of us are even willing to settle for turbocharged V6s, while we consider anything below four cylinders absolute blasphemy. A hard-to-swallow pill for us as car lovers is the reality of downscaling and taking advantage of smaller motors mated to boosted powertrains, whether forced induction or electrification; Mercedes-AMG has already removed the V8 from its C63 to make space for a plug-in hybrid four-cylinder system, which has left us somewhat despondent.
However, The reality is that this downscaling allows for greater fuel efficiency and more efficient performance, and modern technology means smaller motors are more powerful than ever.
In recent years, the popularity of the three-cylinder engine has risen dramatically, which isn't necessarily bad. Modern technology has allowed three-cylinder engines to compete with the more common four-cylinders and exceed their capabilities. There are even three-cylinder supercars over and above hot hatches and sports cars. Our question, however, is why?
To answer that, we need to look at what makes three-bangers so popular, their benefits, and their weak points.
3-Cylinder Cars: The Basics
While there are a plethora of engine configurations, three-cylinder motors are only ever found in one of these; you only ever get inline-three or straight-three engines. This makes sense, as you can't arrange three cylinders in a V or a W.
The other commonality most three-cylinder engines have is turbocharging. While they can theoretically be run as naturally aspirated engines, the premise of downsizing displacement for fuel efficiency in 90% of use cases is undone under a full-load setting when manufacturers want the equivalent power to the four-cylinder engine the three-pot replaces. Turbos are an easy way to do this, as you can run them in most situations with little to no boost and get the full fuel economy benefit.
The size of a three-cylinder engine, or its displacement, is also limited. A combustion chamber's shape and size significantly impact its ability to generate power and be efficient. Too large a combustion chamber results in incomplete combustion, whereas too small a combustion chamber would produce too little power and torque. So automakers typically hover around the 300-500cc mark per chamber, resulting in 0.9-1.5-liter three-cylinder motors. There are, however, outliers to this.
Pros of 3-Cylinder Engines
- Compact and Lightweight: Lower displacement and fewer cylinders typically mean a smaller physical footprint for the engine, meaning it can be oriented longitudinally or transversely with ease and in both front- and rear-engined applications. Not only are these engines smaller and easier to package, but they weigh less too. Less weight has big benefits for handling and fuel economy.
- Fuel efficiency: Larger engines are typically less economical across low-load use. You burn fuel unnecessarily to trundle along at steady speeds and only require the extra displacement for high-load acceleration. By cutting down on displacement, three-cylinder engines consume less fuel in most situations. Believe it or not, frictional losses created by the cylinders within the cylinder block are lessened thanks to the reduction of cylinders.
- Cheaper manufacturing: Fewer cylinders mean fewer parts, resulting in cheaper production and easier repair jobs.
- Unique sound: Although not appealing to all, the three-cylinder engine generally produces a unique sound reminiscent of a flat-six.
- Reduced emissions: Nowadays, especially in Europe, carbon emissions are a great worry to governments and environmentalists. This has recently contributed greatly to the electrification of the motor vehicle and downsizing of many engines, thus keeping emissions to a minimum. Although not really affecting us directly, it's nice to know our cars are less harmful to the planet and produce less pollution.
- Comparable performance to four-cylinders: Because they are so close in displacement to four-cylinder motors, three-pots are able to provide similar performance, even if they need to resort to more boost pressure to compensate for less displacement.
Cons of 3-Cylinder Engines
- Noise and vibration: Although the three-cylinder engine itself may sound cool, it lacks the smoothness and refinement of a four-cylinder engine. Because it is less balanced, it creates a rocking motion and requires balancers to keep everything running smoothly. Despite this, it can create harsh vibrations, particularly at low RPM. It's particularly noticeable when idling, where they sound more like golf karts than traditional cars.
- Low power: While we said that three-cylinder engines produce comparable power to four-pot motors, a larger displacement engine of the same architecture with the same amount of boost, etc., will always produce more power. It's as simple as that, and in reality, there is no replacement for displacement when all other conditions are the same.
- A new learning experience: If you're used to driving other cars, inline threes may take some getting used to. They can be noisy, but you also have to rely more heavily on boost and know when and where peak power and torque will arrive.
Rumors About 3-Cylinder Engines
As with any technology, some rumors abound, often without foundation.
- Are three-cylinder engines unreliable?
This rumor persists based on a few threads of logic. One is that in order to get the same outputs as a four-cylinder motor, inline threes need to be overstressed. The other is the element of noise and vibration that we've already mentioned as a con of this configuration. The truth is that these engines go through millions of hours of development and use newer construction technology to ensure they are as reliable as larger motors when maintained and looked after correctly. Balancing shafts help compensate for the roughness and prevent the engines from shaking themselves to pieces. Tuners even get big power figures from them, and without major modifications or long-term reliability issues.
- Three-cylinder engines are only suitable for small sports cars, mostly Kei cars.
These small engines predominantly became popularized through Japan's Kei car scene, as they were extremely small and fuel-efficient. The fact of the matter is, however, these engines are more than sufficient for hatchbacks and even some sporty variants of cars. They are now found in a broad array of vehicles and have been used in compact crossovers, hatchbacks, sports cars, and even a hypercar.
3-Cylinder Cars
The list of three-cylinder cars is ever-expanding, ranging from an array of economical city cars and V8-beating hot hatches (around a race track and down the drag strip) to sports cars and hybrid supercars.
Although not as refined in budget cars and not always able to replace the roar of larger displacement engines, you cannot deny the versatility of a modern car powered by a three-cylinder. Don't believe us? Well, here are just a few examples of three-cylinder cars currently in production showcasing just how broad the spectrum of use is for the humble straight-three.
MINI Cooper Hardtop
The beloved little Mini Cooper from the BMW Group is powered by a turbocharged 1.5-liter inline-three, boasting a respectable 134 horsepower. It's not particularly slow either and will dash from 0-60 mph in just 7.6 seconds; not bad for an “entry-level” car from Mini. This isn't a performance car per se, but rather a more premium alternative to other city cars found within the market today. And, this engine has even been used in other BMW Group cars including the 3 Series in some markets.
BMW i8
Although no longer in production, the i8 was BMW's early attempt at becoming more environmentally conscious while still being sporty. The goal for the i8 was simple: be a stand-out BMW sports car but produce small-car fuel economy. Powered by a mid-mounted 1.5-liter turbocharged engine (the same one from the Mini above) and a supporting 141-hp motor at the front, the i8 boasted a near 50/50 weight distribution and a range of 300 miles when combining both power plants. Being a plug-in hybrid, you need not worry about running low on gas or a drained battery. And it had butterfly doors which made it infinitely cool to look at.
Some may lament the i8 as not a true sports car or one that had the looks but not the substance, but it was a hybrid sports car at a time when no one else dared to brave these waters, so should be seen as a stepping stone to some of the other cars on this list.
Toyota GR Corolla
Toyota's Gazoo Racing (GR) department has grown in popularity in recent years, putting an end to the spell of boring cars Toyota once produced and building cars for enthusiasts once more. Toyota is even in the top three best-selling sports car manufacturers in America.
Today, we get to enjoy an array of performance GR variants with manual gearboxes, sexy designs, and multiple engine configurations, including inline-sixes, flat-fours, and yes, a turbo three-cylinder. The Corolla, AKA the best-selling car worldwide, got treated to the GR makeover. The result was the Toyota GR Corolla, generating 300 hp and 273 lb-ft of torque (295 lb-ft in Morizo guise) from a turbocharged 1.6-liter three-cylinder engine sent to all four-corners by a rally-derived AWD system and a six-speed manual gearbox. 0-60 mph takes 4.99 seconds in standard form and 4.92 with the extra torque, stickier tires, and shorter gearing of the Morizo Edition.
Koenigsegg Gemera
Christian von Koenigsegg is no stranger to innovation and out-of-the-box thinking. Whether it's record-setting speed, the fastest-revving V8s in the world, the direct-drive system of the Regera, or the automatic-but-also-a-manual gearbox in the CC850, he's a man who knows how to engineer something crazy.
The Gemera is exactly that – something crazy. It's a four-seater hyper-GT with two massive Koenigsegg Automated Twisted Synchrohelix Actuation Doors (KATSAD). It's also a 1,727-hp hybrid hypercar, with the combustion component comprising a 2.0-liter three-cylinder engine with camless valve technology. The three-cylinder is called the TFG, or Tiny Friendly Giant, and it can generate as much as 600 hp on its own and run on renewable ethanol.
Adding to its craziness, the mid-mounted engine is longitudinally oriented and drives the front axle. Three electric motors assist it in doing its business, and by business, we mean 0-62 mph in 1.9 seconds and a top speed of 248 mph. Insane? Yes. Utterly brilliant? Also yes.
3-Cylinder Cars Still Sold In America
While not dominating the market, there are still a ton of three-cylinder cars still sold in the US:
- 2024 Chevrolet Trax
- 2024 Chevrolet Trailblazer
- 2024 Buick Envista
- Buick Encore GX
- Mini Cooper Countryman
- Mini Cooper Hardtop
- Mini Cooper Convertible
- Mitsubishi Mirage
- Mitsubishi Mirage G4
- Koenigsegg Gemera
- Toyota GR Corolla
- Ford Escape
- Ford Bronco Sport
- Nissan Rogue
- Karma GS6
Forbidden 3-Cylinder Fruit
Being America, not every fancy, popular, and cool three-cylinder hot hatch made it to our shores, and there is certainly an abundance of small cars we'd love to see in the USA. But we'd be remiss not to mention some of the great three-cylinder cars available elsewhere in the world that we can't get stateside.
Ford Fiesta ST
Disappointingly, Ford decided to retire the Ford Fiesta ST in 2019 for the American market. At that time, it had a turbo 1.6-liter four-cylinder and was a laugh-a-minute hot hatch we miss every day.
The ST that replaced it capitalized on everything that made the previous gen so incredible but turned it up to 11… at least in every department except for the cylinder count, which got turned down to just three. 1.5 liters big and with a turbo strapped to it, it generated as much power as the outgoing ST200 – 197 hp and 214 lb-ft. 0-60 took 6.5 seconds, and it handled like a hyper-aggressive puppy on acid. It was hilarious to drive, and could even shut off a cylinder when cruising under low throttle loads to save even more fuel.
Toyota GR Yaris
America might get the 300-hp GR Corolla, but that wouldn't exist if it weren't for this, the GR Yaris. Originally developed to participate in the WRC, the Yaris was where Toyota developed the 1.6-liter turbo three-banger and epic AWD system. But a change in the rules meant it couldn't go racing as planned, so Toyota did what any gearhead-led car maker would do – it put the race car into production.
Its three-cylinder motor is less powerful than the Corolla's, with up to 268 hp in most potent form and 273 lb-ft in GRMN guise. Despite this, it's capable of a sub-six-second dash to 60 mph and a top speed of 143 mph. It's a proper pocket rocket, and through Toyota's Kinto Factory program, you can keep upgrading it throughout its lifespan.
The GR Yaris is proof that three-cylinder engines can produce big power reliably, too, and a tuner recently managed to crank out 740 hp from a modified GR Yaris with a stock bottom end.
Keyword: 3-Cylinder Cars: Proving That Downsized Performance Can Still Be Fun