It all comes down to packaging, as fitting a hybrid four-cylinder engine widthways in the nose of front-wheel drive cars "has its limitations", according to Heil. For bigger, rear-drive Mercs, it's not such a problem, as even hybrid fours can be fitted longitudinally, but certainly A-Class, B-Class, CLA and GLA models in years to come will feature the distinctive grumble of three pistons.
Anything else?
Heil also confirmed that Mercedes was working with Renault on a small petrol engine, following on from the 1.5-litre turbodiesel it sources from the French firm for its compact cars. However, whether it's a three-cylinder engine designed to go in a hybrid or a conventional joint venture four-cylinder, we're unlikely to see any of these powerplants before late 2016.
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