Mazda's Sky engines and gearbox

There are pretty cars on Mazda's stand at the Tokyo motor show the Kiyora for example, but we've already seen this concept car at last year's Paris motor show.

No, it's some new engines that are the big stories from Mazda's stand. The company want to improve the fuel economy of all its engines by 30% by 2015.

So, to kick off, it's developed a new 'SKY-G' petrol engine which uses an advanced direct-injection system that can apply several different settings to maximise economy. There's also a new, low-friction engine block.

New petrol engine is 15% more efficient more for diesel unit
Mazda says that the SKY-G engine will be around 15% more efficient than its current 2.0-litre petrol engine.

Even bigger improvements are claimed for the new 'SKY-D' diesel engine.

The engine has a low-friction engine block, but gets a two-stage turbocharger and piezo fuel injectors for up to 20% better fuel economy than the company's current 2.2-litre diesel engine.

SKY-Drive is a new transmission and aims to bring a 5% increase in fuel economy and a 'more direct, sporty feel'.

These engines and gearboxes won't be available until 2011.

Weight-loss programme for all Mazdas
To achieve the 30% fuel reduction target, all Mazda's will have to go through a weight-loss programme. From 2011, cars will be at least 100kg lighter than current models.

Weight loss isn't achieved by staying away from pies, or by using expensive lightweight materials. Mazda says by 'pursuing the perfect structure', developing new machining and welding technology and replacing heavy materials, such as steel, with aluminium, magnesium or plastic.

Things won't stop there either. From 2016, the company will aim to reduce their car's weight by a further 100kg.