The i40’s mechanical make-up conforms to the class norms. Hyundai offers two different four-cylinder engines that are mounted transversely under the bonnet and drive the front wheels.
Power outputs range from 114bhp for an entry-level 1.7-litre diesel, through to the range-topping 140bhp version of the same engine. That low-power diesel also comes with economy-enhancing technologies that Hyundai gathers together under its ‘Blue Drive’ banner.
An automatic engine starter-generator, intelligent alternator, low-resistance tyres, a gearchange indicator and an automatic radiator blank all combine to lower its emissions to just 110g/km and boost fuel economy to 65.7mpg on the combined cycle.
That makes this Hyundai one of the most frugal family cars you can buy at the moment. From a car manufacturer that, until quite recently, had very little experience in producing diesel engines at all, that’s quite some achievement.
Few will hope for more than average outright performance from a big diesel semi-estate like the i40. Good mechanical refinement, good fuel efficiency, reasonable accelerator response, decent grip and a strong and progressive set of brakes will surely satisfy most expectations – and in most of those areas the i40 does that.
Perhaps most impressive is how quiet its 1.7-litre common-rail diesel engine is during typical use. When we originally road tested the i40 at Mira, our test car seemed far more hushed than other diesels in the class, and that’s confirmed by our noise meter readings; the last generation 2.0 TDI Skoda Superb was 8dB noisier at idle.
That base i40 is also much more responsive than some economy-biased rivals. Fitted with a shorter final drive ratio than its more powerful diesel sibling, and with an engine that produces peak torque from just 1250rpm, our i40 responded quickly to the accelerator pedal and with enough outright urge to suffice in most everyday situations. Our tests also suggest that it’s slightly quicker than Hyundai’s official claims; 12.9sec to 62mph seems a little conservative, given that we recorded an average 12.2sec dash to 60mph.
For those who desire greater performance, the 140bhp version of 1.7-litre diesel is claimed to dispatch the benchmark sprint around two seconds quicker. However, opting for the higher-powered variant results in a CO2 penalty of 4g/km, which isn't too considerable if the i40 is being considered as a company car purchase.