Currently reading: Future cars will get bigger engines due to real-world emissions tests
Reports say car makers will ditch smaller capacity units for larger ones as new emissions tests expose flaws
Sam Sheehan
2 mins read
14 October 2016

Car makers such as Volkswagen, Renault and Vauxhall will slow the development of downsized engines and bring back larger capacity units following the introduction of new emissions tests, according to reports on Reuters.

Reuters says that the implementation of new real-world testing procedures has exposed flaws in downsized engines, which were predominantly developed to achieve low emission ratings in older laboratory tests.

New real-world data has shown that downsized units can sometimes perform worse than larger ones for CO2 and NOx output, largely because of the heat generated by their turbos, which they depend on more to develop power.

While lab tests were unable to reveal these downfalls, new real-world testing, which will come into force by 2019, shows it more clearly.

Common issues in smaller units include overheating that requires over fuelling to keep engine temperatures cool. This, in turn, results in more unburned hydrocarbons, particulates and carbon monoxide.

Pavan Potluri, an analyst at forecasting company IHS Automotive, told Reuters: "[Downsized engines] might be doing okay in the current European test cycle, but in the real world, they are not performing. So there's actually a bit of 'upsizing' going on, particularly in diesel."

According to Reuters, several car makers have already started to work this ‘upsizing’ philosophy into production models.

General Motors is said to be ditching its 1.2-litre diesel engine, which features in models such as the Vauxhall Corsa, when new 2019 architecture is launched, with the smallest diesel engine in the future range likely to be around 1.5 litres in capacity.

Volkswagen is replacing 1.4-litre three-cylinder diesel engines with four-cylinder 1.6-litre motors in smaller models, and Renault is also making a U-turn by introducing a 10% larger unit in place of its R9M 1.6-litre diesel, which itself was a downsized unit that filled the space left by a discontinued 1.9-litre diesel.

This comes at a time when companies like Porsche have employed downsizing in their models. The new 718 Cayman and 718 Boxter models have been the subject of much discussion following their use of turbocharged four-cylinders in place of the old cars' flat-six motors.

In the future, downsizing might come in the form of increased hybridisation, rather than the shedding of cubic centimetres. Sudeep Kaippalli, Frost & Sullivan analyst, told Reuters "Downsizing will mean you take a smaller engine and add an electric motor to it."

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14 October 2016
Reports say that car makers will say bollocks to nonsense government legislation in the wake of VW gate and the silliness of 1.0 engines with massive turbos last seen on Nelson Piquet's qualifying laps. Like those engines the silly downsized motors need ragging to achieve forward momentum delivering crap mpg and blow up after 100,000 miles ..... good in the lab though.

14 October 2016
Some polite smiling must be going on in Japan today.

14 October 2016
Hopefully this might also mean the return of new 2.5/3.0 V6 engines. Return of the ST220. Insignia GSI, would slot in nicely below the VXR. Either would do nicely thanks.

14 October 2016
For years we have read of the Fiat 2 cylinder getting half its EU test figure in the hands of the magazines, and the Ford 1 litre getting only slightly more. Its been obvious in the real world that over small enegines have to work too hard, nice to see the real world test reveal this. I too would love to see the return of larger engines in normal cars. Mazda look rather ahead of the curve with their slightly larger petrol engines without turbos.

14 October 2016
Could Autocar be kind enough to do an in depth piece on the upcoming European real life MPG and emissions tests? German car makers have a huge political hold in Germany-dominated EU as evidenced by the Volkswagen dirty diesel scandal. Will they let Brussels introduce tests that expose their technical inferiority in the power train department? Really?


14 October 2016's what I've been saying for years.


14 October 2016
... my next car is a V8 twin turbo...

14 October 2016
Couldnt careless. Just renewed the road tax for 12 months on our petrol Twingo Dynamique S, which incidentally does 80+mph down the motorway, cost, a big fat zero.

3 February 2017
In the grown up world, people are often able to look at the bigger picture beyond their own narrow self-interest.

14 October 2016
Downsized engines consume really less in real conditions (with direct injection and turbo). But I'm not really convinced by their reliability.
But the fascination of bigger engines is greater, despite what say journalists. They have to defend their interest.
Porsche and BMW could stop their current stupid engines and make relatively NA flat 6 and L6. And the journalist will say that it's wonderfull.
We can dream.


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