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The other day over at Evo, Antony Ingram wrote an interesting piece regarding the current trend among automakers for downsized engines. Although it’s much more common in Europe, even here in the US automakers are at it. Take the EcoBoost Ford Mustang and Chevrolet Cruze, for example. As Ingram notes, it’s mainly a result of emissions and fuel economy test procedures. These small-capacity turbocharged engines are tuned for the tests, running at low rpm—below the point where the turbocharger kicks in—using little fuel and producing little pollution in the process.

Real-world driving can be a far cry from the test cycle, making it hard to replicate official MPG figures, particularly in city driving. But change is coming. Later this year, new emissions regulations come into effect in Europe, with the catchily named “Real Driving Emissions test.” In part a response to dieselgate, it’s an attempt by EU regulators to correct a system whereby actual car pollution remains a lot worse than it should based on testing requirements.

It’s not hard to understand why we’ve ended up here. Why spend the engineering budget trying to tune a naturally aspirated engine to meet performance and emissions targets when you know you can ace the test and still make that headline horsepower number by bolting on a turbocharger instead? It’s not just mainstream models we’re talking about, either; even Porsche and Ferrari are dropping naturally aspirated engines for smaller-capacity forced-induction motors.