Given the technologically innovative measures it uses to go about its business, this new Skyactiv-X engine sounds and feels surprisingly ordinary during day-to-day use.
When we originally road tested the Skyactiv-X, we noted that there was a vaguely rough, diesel-like edge to its timbre at idle and when accelerating through the lower reaches of the rev range, which morphs into a slightly coarse four-cylinder buzz as the crankshaft spins up to the 6500rpm limiter. Otherwise, it behaves like a pretty typical normally aspirated engine. It may be ground-breaking in what it does, but doesn’t feel much that way in how it does it. Later versions seem to be smoother but no more characterful
There are two distinct sides to its power delivery. It’s very happy to potter about at exceedingly low revs, with no buzzing or groaning to indicate you’re lugging the engine. That gives the impression of torqueiness, but sadly it’s only an impression because when you put your foot down for a bit more acceleration, it’s got very little to give unless you shift down several gears and send it to the redline.
The engine will oblige with linear acceleration and good throttle response, but due to the long, economy-optimised gearing, that redline is long way away and as the revs climb, there’s little sense of high-rev vigour to report on. It simply does not feel like it makes the claimed power figure.
Our timing gear supported that. The Mazda’s 0-60mph time of 9.1sec was slower than the supposedly less powerful Mercedes A200 (7.8sec) and Volkswagen Golf 1.5 eTSI (8.3sec). Admittedly we did test both those rivals with automatic transmissions, but that excuse doesn’t apply for the in-gear acceleration figures. In fourth, the Mazda required 14.2sec to accelerate from 30mph to 70mph, whereas the turbocharged Mercedes and Volkswagen did it in 9.6sec and 9.1sec, respectively.
We’ve not performance tested a later, updated Skyactiv-X, but it doesn’t take timing gear to notice that its six additional horses haven’t made a huge difference to the raw performance.
We would probably stick with the cheaper Skyactiv-G, which, despite a 63bhp deficit, doesn’t feel an order of magnitude slower in everyday driving. After all, the difference in torque is far smaller, at 20lb ft.
The Mazda claws back some ground by virtue of its delightful manual gearbox. The throws are not quite as short and mechanical as in the Mazda MX-5, but just comparing it to one of the greatest manual shifts you will find at any price should tell you how good the 3’s is. Every gear engages positively but without balking, and you can perform fingertip changes, or flash the lever through as you see fit.