Trend-tracking: The 3-cylinder turbo engine – a mouse doing a man's job?

If someone told us a few years ago that a tiny 3-cylinder turbo engine will take over the job of the bigger 4-cylinder someday, we would have doubted this… sure, in a small car, but definitely not in a small SUV or midsize hatchback, surely?

How could the traditional tried and trusted 4-cylinder be improved, by replacing it with a fewer cylinders to do the work, and a smaller engine capacity?  Turbo engines have advanced so much, and have become so widely used across many vehicles, that for some advanced manufacturers this is the only engine they offer.

We have become used to the idea of the small 3-cylinder engine in a city car – the Daihatsu Charade of the 1980s was the 1st 3-cylinder engine South Africans were introduced to, in this compact hatch.  For years the 3-cylinder was forgotten, and then the Daewoo Matiz arrived with its 796cc 3-cylinder engine.  Then in the year 2006 the Toyota Yaris T3, Citroën C1 and twin Peugeot 107 re-introduced the 1.0 3-cylinder engine, followed in 2007 by the introduction of the then-new Daihatsu Charade and Chevrolet Spark (which is the Daewoo Matiz re-badged, which became Chevrolet Spark Lite).  2010 saw the first turbodiesel 3-cylinder in the VW Polo BlueMotion.

It was Ford who surprised the world with its 3-cylinder EcoBoost engine to be fitted in the Ford EcoSport!  Although a small platform, it is a compact cross-over – will this engine be able to pull this size vehicle? It is only 999cc.  Thanks to the clever integration of a turbo it does its job well, and the EcoSport with EcoBoost engine is now an accepted form of motive power.  The EcoBoost engine won the International Engine of the Year Award, and is now also available in Fiesta.

Another shock was the introduction of the Renault Clio 4.  Renault has been working the turbo petrol magic for many years, but usually reserved for performance cars such as Megane RS.  When the company announced that new Clio can be had with the 66kW 3-cylinder turbo engine (no indication of engine size, with only a small “turbo” badge on the tailgate) we knew something was coming… 898cc.  Clearly the buying public would have been very sceptic if they badged it 0.9 in a car the size of Clio, so merely sticks to a name reference of 66kW turbo.

MINI was also the talk of the town when it introduced the new MINI hatch, giving its Cooper derivative a 1.5 turbo 3-cyl engine.  Where the previous MINI-by-BMW Cooper S were supercharged and then turbocharged, the S models were the ones to have, no doubt… but many who drove both new Cooper and Cooper S (both turbo) reckon the Cooper is now the one to have.  BMW even uses this 1.5 3-cyl in the 218i Active Tourer, which is an MPV.

At the top of the 3-cylinder hierarchy sits the BMW i8 – this electric-hybrid supercar employs a serious electric motor, combined with the same tiny (for its looks and performance) 1.5 3-cylinder!

Last week saw the local launch of the new Peugeot 308.  Remember this is a mid-size hatchback, competing in the Golf class.  Volkswagen was the first to be brave by putting a 1.4-litre TSI engine in the Tiguan compact SUV and then in Golf 6 back in 2009, followed by a 1.2 in Golf 7 for in 2013.  But in 2015, Peugeot beats the rest by being the 1st 3-cylinder engine in this mid-size car to be offered locally.  The PureTech 3-cyl turbo engine is offered in 81kW 205Nm guise or 96kW 230Nm in the Peugeot 308 GT Line.

What’s more, Ford will be introducing the Focus (same size as Golf and 308) this week, using the EcoSport/Fiesta’s 1.0 EcoBoost 3-cylinder too!

What makes the 3-cylinder turbo so clever and desirable?  For the same reasons that V10s change to V8s, and V8s are replaced by 6-cylinders – the fewer cylinders that need fuel fed to them, the less fuel is used.  Simple.  Fiat even sells a TwinAir 2-cylinder engine in the current Fiat 500, but it won’t be coming to SA.

Where almost all 4-cylinder engines sound a bit bland (often spruced up by special exhaust trickery) the combustion cycle of a 3-cylinder gives a gravelly and charismatic engine sound, which contributes greatly to driving pleasure.  A 3-cylinder turbo is on par with 4-cylinder turbo engines, or the more traditional 1.6 / 1.8 / 2.0 un-boosted engines.  This little mouse really can do a man’s job.

So the 3-cylinder turbo petrol engine is the way the industry is going, and we as car buyers benefit, in power, fuel efficiency, and engine sound.  3 hurrays for 3 in a row!