MAZDA3 GSE SKYACTIV

But I think it’s fair to say that those who do the right thing often like to be seen to be doing the right thing. That’s part of the appeal of cars like the Toyota Prius hybrid and the new Nissan Leaf electric car. They boast next-generation eco-technology, but they also make a statement to the outside world that you’re doing your part to save the planet.

Mazda is banking on its buyers being a lot more altruistic than that with its new Mazda3 GSE SkyActiv. It’s not about game-changing tech-trickery, but make no mistake: this car represents a complete rethink of existing engine and transmission technology and lays the foundation for the company’s next generation of models – both the forthcoming CX-5 crossover and new Mazda6 will both embrace the SkyActiv technology you see here – and bring even more. Or rather can’t see, but the GSE really looks no different from the Mazda3 GSX on which it is based.

The best way to demonstrate what this new engine/transmission technology has achieved is to compare the Mazda3 GSE SkyActiv with the standard GSX. Both have 2.0-litre petrol engines and automatic gearboxes and are broadly designed to do the same job. The GSE SkyActiv makes 113kW/194Nm, drives through a six-speed gearbox and achieves combined fuel economy of 6.2 litres per 100km. The GSX offers 108kW/183Nm and manages 8.4l/100km. Granted, the Mazda3 has always been regarded as one of the thirstiest (if most entertaining) cars in its class, but the SkyActiv’s thrift really does support Mazda’s claim that it’s a petrol car with the economy of a diesel.

How’s that done then? In typical Mazda fashion, it’s conventional technology but with every major component and process rethought and reshaped. The SkyActiv engine has much less internal friction than the standard 2.0-litre, with redesigned pistons, connecting rods and conrods. It runs very high compression – 12:1 for New Zealand to allow the use of 91-octane fuel, although the same car in Europe runs a remarkable 14:1 ratio. Multi-hole injectors assist in achieving the most efficient combustion possible.

The SkyActiv six-speed gearbox is a conventional automatic in principle, but Mazda claims it’s just as quick and fuel-efficiency as fancy dual-clutch systems like Ford’s Powershift and Volkswagen’s DSG. Internal friction has been vastly reduced, the torque converter locks up at 5km/h and it’s been equipped with a unique stop-start system that uses the compression of the engine to kick the powerplant into life when required, by stopping the pistons at exactly the right place when the engine shuts down at traffic lights. Clever.

The GSE SkyActiv has exactly the same specification as the mid-range GSX and costs $2100 more, at $37,395. Your money doesn’t buy a status symbol – although there are some nice blue badges on the outside of the car. However, the SkyActiv is even more engaging to drive than the standard Mazda3, which is high praise indeed as it’s arguably the sportiest mainstream small-car around.