This text was not translated, because it is originally in English New I-4 engines show major economy improvement over I-5 predecessors. The relentless push toward engine downsizing continues with Volvo's introduction of its Drive-E I-4 turbocharged engines in its 2015 models. Although not yet officially posted to the official Fueleconomy. gov EPA site, Volvo is claiming fuel economy up to 25 city and 37 highway for the S60 and V60 models equipped with the new 2. 0-liter turbocharged engines. Assuming these figures are not adjusted downward under final EPA scrutiny, they represent an improvement of 4 mpg city, and a whopping 7 mpg highway over the 2014 S60 with the five-cylinder engine.