Honey, I shrunk the engine - how small can be better for you

  • Peugeot 1.6-litre 270THP (308) – 169hp/litre
  • BMW 1.5-litre three cylinder (i8) – 154hp/litre
  • Ford Ecoboost 1.0-litre (Fiesta) – 140hp/litre
  • Honda 1.0-litre VTEC turbo (Civic) – 129hp/litre
  • Fiat MultiAir 1.4 turbo (Abarth 124 Spider) – 121hp/litre

Big cars with small engines are becoming popular, and for anyone old enough to get the reference to Disney’s 1989 sci-fi classic movie, the idea of a luxury car with less than 2.0 litres may be hard to accept.

Yet the reality is that clever technology and advances in materials have allowed significant increases in specific output – power for a given capacity of engine – inherently linked to efficiency.

Surprisingly small engines in unlikely cars

Ford Mondeo Estate Zetec 1.0-litre

Ford Mondeo Estate

We haven’t made a mistake – Ford’s largest family car is available with an engine size that once would have shamed the smallest superminis. It’s a three-cylinder turbocharged unit producing 125hp and 170Nm, and faced with the 1,476kg weight of the 5.0m-long estate it can reach 62mph in 12.1 seconds and go on to 121mph. Emissions, at 120g/km, are higher than the greenest diesel option offered.

Ford EcoBoost 1.0 Engine

Although behind the class average, performance is adequate for British roads if you can tolerate the audible effort being made – and the real compromise made is in towing capacity, which drops from 2,000kg for the 2.0 litre to 900kg. Even then it’s not the weakest hauler in the range, as the 1.5-litre TDCI can only pull 400kg.

New price: £19,785
CO2: 120g/km
Claimed economy: 62mpg
Metres/litre: 5m/litre

Peugeot 5008 1.2-litre PureTech 130hp

Peugeot 5008

Once, the sight of a 1.2 badge on the rear of a small car such as a Vauxhall Corsa would suggest until it was safe to pass, progress would be slow. Putting that capacity of powerplant into a tall seven-seater SUV would surely be enough to fill any driver with dread.

Peugeot’s 5008 1.2 PureTech 130 is one of the new breed, however, and the three-cylinder unit puts out a healthy 130hp and 230Nm. Fully occupied, it isn’t exactly fast, but 10.9 seconds to 62mph is more than adequate for an economical family car.

Read our long term test review of the Peugeot 5008 GT Line 1.2 PureTech here.

New price: £19,210
CO2: 117g/km
Claimed economy: 55mpg
Metres/litre: 3.9m/litre

Volkswagen Tiguan Allspace 1.4 SE Nav

Volkswagen Tiguan Allspace

Another seven seater with diminutive displacement, the Tiguan Allspace is a large SUV-esque crossover. Under the bonnet you can find either a 2.0 TDI with 150hp to 190hp, or a 1.4-litre TSI producing 150hp.

Only available with front-wheel drive, the petrol option produces more CO2 and uses more fuel than the similarly rated diesel, and has 90Nm less torque to move the 1,535kg body around – and that’s before you’ve filled the seven seats with passengers. Even so, it can reach 62mph in 9.2 seconds, marginally faster than the diesel, and is a useful £2,490 cheaper too.

New price: £29,515
CO2: 137g/km
Claimed economy: 46.3mpg
Metres/litre: 3.3m/litre

Volkswagen Arteon 1.5-litre TSI

Volkswagen Arteon

The Arteon is a long, low-slung fastback hatch in the style of the Mercedes-Benz CLS or BMW 4 Series Gran Coupe – bigger than a Passat and with an aggressive fascia designed to encourage slower cars back into the inside lane. Inside, equipment and comfort are as you’d expect for a car that starts at £31,885 and occupies a recently created luxury niche.

What you might not expect is the four-cylinder 1.5-litre engine. Dubbed 150 EVO, the latest revision of that pioneering 1.4 TSI can be found in a wide range of cars from VW, Audi, Skoda and SEAT. As the name suggests, it produces 150hp and an impressive 250Nm, and the Arteon so equipped will reach 62mph in 8.7 seconds.

New price: £31,885
CO2: 119g/km
Claimed economy: 54mpg
Meters/litre: 3.2m/litre

Audi A5 1.4 TFSI

Audi A5 Coupe

Company car drivers love the Audi A5 – spacious enough for families, but stylish and instantly recognisable as a luxury coupe. With a 3.0-litre V6 and quattro four-wheel drive, there’s very little that can approach the flexibility and competence of the two-door Audi, and that’s what the drivers hope their car projects regardless of trim or engine.

Audi 1.4 TFSI Engine - transverse installation

However, not every A5 you see is a high achiever of torque and grip. Making the low-cost lease headlines, there’s a 1.4-litre option. Powered by – you’ve guessed it – a turbocharged, direct injection petrol four-cylinder with 150hp and 250Nm outputs, it can reach 62mph in 8.9 seconds.

New price: £35,495
CO2: 125g/km
Claimed economy: 52mpg
Metres/litre: 3.1m/litre

BMW 318i

BMW 3 Series

The BMW 3 Series is the default company car for many people, and bragging rights for a big engine go with the territory. Much of the car’s image was built on the compact saloon’s six-cylinder power and performance, after all.

So the biggest, safest and most well equipped 3 Series yet must surely have the biggest engines, too? Far from it – under the bonnet of the misleadingly-titled 318i is a three-cylinder 1.5-litre unit that produces 134hp and 220Nm – not far off the yuppie-era high-spec 323i.

If that seems a little low output in this company, look to the i8 – where as part of a hybrid powertrain for the alternative-fuel supercar, a highly tuned version of this petrol motor contributes an impressive 231hp.

New price: £27,800
CO2: 141g/km
Claimed economy: 45mpg
Metres/litre: 3m/litre

Mitsubishi Eclipse Cross 4×4

Mitsubishi Eclipse Cross First Edition

Unusual styling helps the Eclipse Cross stand out in a growing crossover segment, but there’s a lot more to it than being just another tall hatchback. Underneath all-wheel drive models is a proper 4×4 setup with advanced stability and grip controls, related to the system found in the impressive Lancer/Evo rally cars.

It has proper ground clearance, too, and despite a rather tall, square front and tipping the scales at 1,550kg, it will sprint to 62mph in 9.5 seconds.

Even more surprising then that in the UK, it’s only offered with a 1.5-litre engine. Producing 163hp and 250Nm, it’s paired to four-wheel drive via a CVT automatic gearbox to keep it at peak torque or efficiency.

New price: £25,605
CO2: 159g/km
Claimed economy: 46mpg
Meters/litre: 2.9m/litre



History of pint-sized engines: from Kei-car to Crossover

As it turns out, there is a replacement for displacement – technology. Although the current smorgasbord of tiny turbocharged petrol engines appears to have popped up overnight, the development of today’s powertrains has been a global effort that began around the same time as those feel-good ’80s films first aired…

Daihatsu Mira

Back in the 1980s, Japan’s strict regulations on city cars kept the popular sub-supermini Kei class down to 550cc, without a cap on power output. Aspirational buyers and the rise of the hot hatch meant serious competition, with Daihatsu and Suzuki developing turbocharged 64hp all-wheel drive marvels like the Mira TR-XX, that could hit 62mph in a little over 10 seconds and approach 100mph.

A specific output of 114hp/litre before 30 years of technological development shows the expertise that also allowed Japan to take the lead with larger displacement turbocharged engines – pursuing American and European markets involved a different priority though, as the 21st century approached.

Economic downturn pushes economy up

Global economies underwent recession through the 1990s, leading to an increased focus on reducing fuel consumption; hand in hand with lower emissions the solution was to dispense and use fuel more efficiently. Injecting precise amounts of fuel directly into the cylinders, began to enter the mainstream.

Mitsubishi Carisma GDi

One of the earliest examples was the Mitsubishi Carisma 1.8 GDi, marketed as 2.0-litre performance, and 1.6-litre economy. It worked, too – the 1,180kg Passat-sized hatchback matched – even exceeded – the performance and consumption of lighter, smaller fuel-injected ’80s cars like the Golf GTI.

The unassuming Carisma did not look like it was hiding technology crucial to the future of petrol engines, but it proved the concept worked.

Volkswagen puts it all together

Volkswagen Golf GT twincharge 1.4 170ps

Small displacement with supercharging or turbocharging and petrol direct injection worked in isolation. Volkswagen combined them all – supercharging, turbocharging and fuel stratified injection – in 2005 for the Golf GT. A 170hp 1.4-litre TSI allowed the heavy (1,300kg) hatchback to hit 62mph in 7.9 seconds.

This novel approach suited emissions based taxation as well as capacity-based; the 170hp 2.3-litre Golf VR5 it replaced produced 211g/km, the 1.4-litre TSi 174g/km.

For the next decade the competition came from within though. Big, torquey diesels with low consumption and low CO2 emissions (or not, as would become apparent) were cheaper, simpler and more popular.


Fashion victims: diesel scandal clears the road ahead

In 2015, various manufacturers were revealed to have been gaming the system for emissions testing diesel vehicles – programming engine management to unrealistically reduce output during test conditions.

This ensured a consumer backlash against diesel (and lawsuits in America), and a harmonised global emissions testing programme that aims to give more realistic figures. Downsized displacement petrol engines are a vital part of a manufacturer’s range, too – China’s growing market incentivises cars below 1.5 litres.


Could your next big car have a small engine?

Is a tiny turbo petrol engine a substitute for a big diesel? With few compromises in terms of power or refinement, the low displacement petrol turbo engine has finally come of age for the mainstream. Petrol engines produce less NOx and far fewer particulates than diesel models, too, so if you care about environmental health there’s a good argument for ditching diesel.

Driving style has a greater influence on economy though, and to achieve those optimal figures most of the cars above will need a gentle touch and slow progress. Read our in-depth reviews and long-term tests to find out more, then use the Parkers Car Chooser to select the best model for you.