Mazda

Despite its reputation for technical innovation, Mazda has been slow to adopt eco-friendly modifications. But that’s all set to change with the company’s new stop-start kit.

Unlike most manufacturers which use off-the-shelf idle stop set-ups, Mazda has developed its own, called i-stop. Bosses claim the unit is twice as quick as rival products, restarting the engine in a mere 0.35 seconds.

Nevertheless, it’s designed to work only with direct injection engines mated to a manual transmission. That means it’s currently available solely on the 2.0-litre petrol Mazda 3 Sport. The result is respectable CO2 emissions of 159g/km and fuel consumption of 41.5mpg.

Eco-minded buyers would, however, be better off with the 1.6-litre diesel version, which manages 119g/km and 62.8mpg.

Elsewhere, Mazda’s efficiency efforts have concentrated on weight-saving, with engineers following a ‘gram strategy’ approach to new model development. So far, results have been remarkable, with the latest Mazda 2 weighing nearly 100kg less than its predecessor.

When the lightweight supermini is fitted with the 1.4-litre diesel powerplant, it puts out 107g/km of and returns 68.9mpg.

At this year’s Tokyo Motor Show, Mazda displayed a number of eco-friendly concepts. Fans saw the new SKY-G direct-injection petrol and diesel engine, which can be mated to i-stop and regenerative braking. Also on the stands was the hybrid Premacy Hydrogen HE, which mixes a gas-powered Wankel rotary unit from the RX-8 coupé with an electric motor.