How European Fuel Economy Testing Will Kill The Naturally Aspirated Engine

While Americans are still asking whether it’s even wise to buy small turbocharged engines instead of larger naturally aspirated ones, we in Europe are slowly losing our ability to even choose a car without a turbocharged engine. Volkswagen has recently announced that it is going turbo only – but in our market, the transition is nearly complete. Except for base engines in Polo supermini and Up! city car, basically everything else has a turbo slapped on it – and it looks much the same with other VAG brands. Others are following closely – Ford eliminated most of its naturally aspirated engines, except for the base 1.6 in Focus and small engines in Fiesta. Renault is coming with new tiny turbo plants to replace small four cylinder NA motors – and is even introducing them to its low-cost brand Dacia. PSA, Fiat, Opel and others are heading this direction as well.

But, why is that? Is it that Europeans are more forward thinking, more interested in economy an environment than polar bear killing ‘murricans with their massive V6s and V8s? Is it the European driving style and road network, requiring smaller and lighter cars?

I think it is neither of these. And every time I hear or read Americans ranting about how the CAFE standards changed the vehicular landscape of the US of A, I imagine how European cars would have looked were it not for nosy European bureaucrats interfering with them.

It started decades ago with taxation. The government needed to find some way to tax the different car differently, so the rich guys with bigger, better and badder cars pay more than the average Joe (or average Hans or Luigi) with his Morris, Topolino or Käfer. They decided that the best way to assess the cars is based on their engine displacement – not horsepower, not weight or dimensions. I don’t want to go to great lengths about why the metric was chosen – but that’s how things panned out.

And since taxation (and eventually, insurance), made it very expensive to own a car with a big engine in most countries, the car makers designed most cars with small engines – not for the sake of efficiency, but just to evade high taxes. Of course, there were still people who could buy expensive cars with huge engines. But having, say, a three-liter, six cylinder car in Europe was always a sign of wealth and extravegance.

The simple fact that it was, and often still is, expensive to own a large-displacement car in Europe, is quite well known and illustrated by atrocities like Ferrari 208 with two-liter, eight cylinder engine offering a scant 155 horsepower (or about as much AMC Pacer of the time). But the secondary result was that by making the high displacement cars expensive to own, no one really cared that much for their economy. Large displacement engines were expected to be power monsters, bought by those who were willing to pay extra for performance. So, if you were to offer anything over two liters of displacement, you tuned it to be extra powerful, letting the owner know where his money went. Which, of course, meant that these engines became really thirsty – while average European 3.0 from 1980s or 1990s offered similar power to American 5.0 V8, it also required about as much gas… or even more, in some cases. There were exceptions, like BMWs ETA low-rpm, low-compression 2.5 litre six cylinder, but they never really caught on.

So, the average European buyer became used to the fact that large displacement automatically means high fuel consumption. As a long-time owner and driver of American cars, I have experienced countless encounters with people who were not willing or able to believe me that my car’s fuel consumption was what I told them it was. I was told that my 1988 Caprice ABSOLUTELY and UNDER NO CIRCUMSTANCES can get a fuel mileage better than 20 liters per 100 km (which is about 10mpg) – because a 2.0 car drinks 10l/100km (about 20mpg) and my engine is more than twice the size.

Which means you can well bring a typical American car with a large displacement engine, which will out-perform most domestic offerings, while getting similar mileage and being much more powerful, but no one will ever buy it. Everyone wants small engines, and no one cares much about what happens with them in a few year’s time. And let’s not even talk about diesels and people willing to spend more than $100k on a luxury sedan, which will lose ¾ of its value in their four or five years of ownership, and then choose a diesel for it just to save a penny per mile.

But, nowadays, there’s worse thing than displacement-based taxation or insurance. Apparently, our planet is warming, or, to put it more precisely, the climate is changing rapidly. Which is hardly a disputable fact. And some say it is our fault. Which is a slightly more disputable fact, and it can be debated to which extent it is our responsibility. So, they decided that we should emit less CO2 from our cars. Which may be a good thing, even just for the reduced fuel consumption and thus less money spent for oil.

So, lots of governments tax cars by the amount of CO2 emitted from their tailpipe, and are fining automakers for exceeding the limits for average CO2 emissions. Which all sounds very nice and dandy, until you see one glorious, gaping hole in the whole scheme.

It is called the NEDC, or New European Driving Cycle. It is similar to American EPA tests, only much worse. You can look at the graph below, showing the speeds of the car during the test. And pay attention especially to the acceleration periods – like 41 second acceleration to accelerate t 70km/h, or 26 seconds to get up to 50km/h. Even a Trabant towing a trailer could do that. And no one would ever drive like that in the real life. Well, unless he is driving a Trabant with a trailer attached. And a brick under the accelerator.

Also, note that the car reaches a VMax of 120km/h during the test (the speed limit on European highways is usually 130) and stays there only for TEN SECONDS. This means two things.

First, no car, ever, can match the NEDC figures in real life. And those are the figures you see not only in ads or brochures, but also in technical documentation. Which means really bad news for anyone with a company car – since you can only use the official fuel economy numbers when calculating fuel costs, the distorted figures will cost businesses money. One could live with that, if the effect was the same on all cars. If you could say ”well, this car gets 4,0 l/100km officially, so I can count on it getting 5,0 l/100km”, all would be quite fine. Only it isn’t.

It is common knowledge that large engines are less sensitive t driving style and load. With horsepower to spare, you can drive fast, with a heavily loaded car, or even tow stuff, and the effect on fuel economy will be relatively small. On the other hand, this also works the other way. Even if you feather the throttle and follow every hypermiling tip and trick, you’re never get a stellar numbers from your V6 or V8. Which means they will perform poorly on the NEDC test.

On the other hand, the turbo engines are perfect for hypermiling. Under low loads, a turbo four is just a little, efficient four cylinder engine, with wonderful mileage. But put it in the car, load it, be heavy on the gas, drive in a hurry – and your fuel economy will be in shambles. However, they perform wonderfully on the unrealistic NEDC test – which happens to be the scenario where they can achieve great mileage.

That doesn’t mean that downsized engines are bad. Something like Volkswagen’s 1.2 TSI/77kW, or Ford’s 1.0 Ecoboost may be a perfectly fine engine, as long as you choose it as an economy-minded power plant, and treat it as such. Those engines can really achieve outstanding mileage figures, but only if they are driven really gently. The effect is most pronounced in company cars – since fleet managers usually tend to buy cheap engines, the sales reps now end up with small engines, revving them to death on the highway, getting mileage on par with a V6 executive sedans, and killing the poor little things in the first 60 thousand miles.

And with NEDC being the basis for official CO2 figures, and CO2 being the biggest target of regulations lately, this problem is only going to increase. In order not to get fined, and to make their cars more attractive to buyers (via advertising great but unrealistic fuel economy figures), who are now burdened not only with displacement-based taxes and insurance rates, but also by CO2-based taxes, CO2 based congestion charges and other “green” levies, car makers will offer ever smaller, ever more complicated engines, shining in NEDC tests, but delivering real-world mileage figures that are increasingly out of touch with reality

I’m more than just a little afraid that in a few years time, naturally aspirated engines will become nearly extinct in Europe. And that anything over two liters will become an extravagance, like it was few decades ago, with power being coaxed from tiny little engines by equipping them with multiple turbochargers and other technical gadgetry. The new breed of turbo car will not be any more frugal, nor any more friendly to the polar bears, because they will be sold and taxed in the glowing light of the NEDC numbers, but ran and fueled in harsh reality of turbocharger operating in high boost.

And Europeans will still scoff at Americans for having their big, thirsty V6s, not caring even a tiny bit about the fact that Avalon V6, travelling on American roads in American pace, gets the real world mileage very similar to the Golf 1.2 TSI, or some other supermodern downsized turbo car about half the size, travelling on European roads, at a European pace.