Many a piece has been written about how the trend of downsizing and turbocharging as a strategy for meeting fuel economy standards is coming to an end, including here on Oppo. Real-world fuel consumption and emissions performance of these downsized turbocharged engines is poor, due to boost enrichment, so automakers have begun looking in other directions, saying that future products (especially in Europe) will actually gain displacement.
So, here’s where it begins - in the lowly Yaris. Toyota’s replacing the 1.3 liter 1NR-FE (which isn’t even turbocharged) with the 2NR-FKE in European-market Yarises. Same engine family, but larger displacement (giving it 12% more peak power and 9% more peak torque), higher compression (improving efficiency), and with wide-authority intake VVT (enabling Atkinson-cycle operation at light load, improving efficiency further).
The engine itself isn’t that interesting - it’s not even new (it’s been around for a couple years now in the Japanese market), the technology is nothing that we haven’t seen anywhere else (Mazda SkyActiv-G engines, for one), and the peak thermal efficiency (38.5%) isn’t even that high compared to where SkyActiv-G is believed to be (closer to 40%), and some other naturally aspirated Toyota gasoline engines are (as high as 41%). And, ultimately, it’s a 110 hp Yaris motor, that gets the thing to 100 km/h in 11 seconds.
What I find interesting about this, though, is that Toyota is claiming that this move - from a port-injected, naturally aspirated engine, to a larger-displacement port-injected, naturally aspirated engine with wide-authority variable valve timing to enable Atkinson-cycle operation at light load - is actually being triggered by Euro 6c and the introduction of the Real Driving Emissions testing regime. If Toyota had to upsize an already naturally aspirated engine and add technology to meet a stricter test on basically the same standard, what does this mean for the aggressively downsized engines with turbochargers and with direct injection, under the new regime?