Small displacement engines with big turbos are all the rage these days and have been for a decade or so but maybe not for much longer, so says a VW boss.
Keeping up with emissions regulations has created the need for small displacement engines, many of which use a turbo to make up for a drop in performance. But if a VW bigwig is to believed, this common practice is coming to a close.
“The reduction in the number of cylinders has achieved its goal. Whether it is moving from four cylinders to three or six to four, then we have achieved efficiency benefits while retaining the qualities of driveability,” VW brand boss Herbert Diess told Autocar.
“That trend made a lot of sense,” he continued. “But it comes to an end now. If we go smaller, we will run into emissions and cost problems.”
Though it may seem like a bad thing for manufacturers to go bigger with their engines, as Toyota is doing with the new Yaris, it may actually help. Many supposedly eco-friendly cars manage considerably fewer miles per gallon than is claimed by the manufacturer.
The problem stems from the current emissions regulation system. Manufacturers are allowed to massage the efficiency of their cars. Mirroring the driving style of an emissions test would mean growing old before you get home.
A stricter ‘real-world’ emissions test is expected to arrive in 2019 in Europe, but scientist John German, who exposed the VW defeat devices used to cheat on emissions, said it will only reduce the number of loopholes manufacturers can use.
Another consideration is the fact CO2 is typically the main focus, but NOx and other particulates can be as harmful, if not more so. Limiting one may have an adverse effect on the level of another.
Diess also addressed the issue of small diesel cars costing a lot more to tax. “For city and supermini cars, it is likely the 48V hybrid systems will replace diesels, offering the same efficiency for less money.”
So is the end of the petrol and diesel engine looming? Diess says no, but the future will contain more help from electric motors.
“The internal combustion engine has a long life ahead of it yet, but as we hit the limits of thermo dynamics, then the cost of hybridisation will be less than that of pursuing the gains without them,” he explained.
Other issues may also speed up the shift towards hybrids and electric cars. Air pollution is said to cause around 467,000 premature deaths in Europe every year, according to the European Environment Agency (EEA), 40,000 of which take place in the UK.
In the wake of the emissions scandal, which wiped billions off the share value of VW, the German manufacturer announced a stronger focus on electric cars.