(Tue 29 Sep 09)

The most dramatic-looking car on the Mazda stand at the Tokyo Show in October will be the Kiyora, a concept intended partly to show what the next generation of small hatchbacks might look like. But the real news is under the skin.

The Kiyora uses Mazda's new SKY-G petrol engine and SKY-Drive automatic transmission. The company has also developed a SKY-D twin-turbo diesel, and if you haven't spotted the naming thread running through all this we have very little to say. The one feature they all share is that they are designed with the aim of improving fuel economy through reduced internal friction; that might not sound very interesting, but it's important because quite a lot of the fuel you put in a car's tank is used up simply by turning the engine and gearbox.

Both SKY-G and SKY-D also benefit from various attempts to improve the combustion process, the broad principle being to create adequate combustion using the smallest possible amount of fuel. Mazda reckons that economy is therefore improved by 15% in SKY-G and 20% in SKY-G compared with current equivalent petrol and diesel engines - or, to put it more dramatically, this technology means that a Mazda3 petrol and Mazda6 diesel would provide similar fuel economy (and of course CO2 emissions) to a present-day Mazda2 supermini.

As well as the reduced friction, the SKY-Drive automatic uses as little transmission fluid as possible and has a revised torque convertor, clutch and lock-up mechanism. There is less slip than normal, leading Mazda to claim that it feels more like a dual-clutch manual (of which examples include the Volkswagen Group's DSG, Ford's PowerShift and Mitsubishi's SST) than a conventional automatic.

Comment on this story on Facebook or Twitter.

Mazda Gallery
Mazda Road Tests

Previous: Reactions To Scrappage Extension                       Next: Hottest Renault Twingo