Fuel tests lead to reverse in downsizing trend

While VW has long used three-cylinder motors in its small cars, it has now declared that it will no longer shrink its engines for theoretical fuel economy benefits.

"We stopped this at Volkswagen," the German car maker's development head, Frank Welsch, insists. "What we have reached now, this is fine. There is not heavy downsizing anymore. Some are calling it rightsizing, but that's not really right, either.

"We will not go lower than 1.0l in a three-cylinder or below 1.5 in a four. The Polo will go to a small four-cylinder engine."

Wishful thinking

The benefits of smaller engines in laboratory testing were often found to be wishful thinking in the real world, especially among more enthusiastic drivers.

The real-world emissions tests in the Equa initiative from Emissions Analytics showed the differences between the official test cycle and real-world tests were particularly large in downsized engines.

The 10 models with the highest percentage difference in the Equa test all used downsized engines, including the Fiat and Alfa Romeo Twin Air 0.9l, two-cylinder engine, the Mini One 1.5, three-cylinder engine and the Smart range of 0.6l, three-cylinder engines.

"People expected too much"

"Downsizing worked for us but maybe in some cases, the approach was too strong," Welsch admitted.

"The extreme of it was too much. Remember what we tried in three-cylinder diesel? It turned out to not be positive.

"The 1.4l three did not work out in the end. People expected too much. We moved back to 1.6 and 2.0l engines with diesel."

Source: Business Day