Currently reading: Mazda plans big efficiency gains
Petrol engines fitted to Mazdas in five years’ time will be significantly more fuel efficient than today’s

Mazda is aiming to lift the efficiency of its petrol engines by 50% by 2020, according to European research and development chief Kenichiro Saruwatari.

The current efficiency of its petrol engines is a competitive 40%, but it hopes to reach 60% in the next five years.

It hopes to do this by developing its homogeneous charge compression ignition technology (HCCI), in which the mixture is ignited by compression rather than a spark, like a diesel.

That will involve raising the compression ratio from about 14.0:1 today to 18.0:1 and achieving very precise control of the combustion process to avoid knock. The aim is to combine the cleaner emissions of a petrol engine with the efficiency of a diesel.

As part of its Skyactiv efficiency programme, Mazda is also investigating scope for reducing heat lost through the exhaust system, which typically loses about 30% of the fuel’s energy. “We’re looking at several solutions but can’t say which yet,” said Saruwatari.

The company has been pursuing its current efficiency path since the development of the 2002 Mazda 6, which was “generation one of the roadmap”, Saruwatari said.He said the next Mazda CX-5 crossover will be the first of the seventh generation. “The main direction of Skyactiv has not changed,” he added, “although we sometimes find new technologies and materials that produce a step change.”

Mazda recently announced a partnership with Toyota that could result in a plug-in hybrid model, but it has said its petrol cars could ultimately match EVs for well-to-wheel efficiency. This could mean average well-to-wheel CO2 emissions of about 80g/km for an unspecified ‘average’ model equipped with a Skyactiv Generation 2 engine.

The third generation of Skyactiv engines could take this even further. Mazda has previously spoken of average well-to-wheel emissions as low as 50g/km, although it has not set a date for this.

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bomb 17 June 2015

I like Mazda for ploughing

I like Mazda for ploughing their own furrow and wouldn't bet against them big strides in real-world petrol economy. It needs to improve mind, I currently drive two cars less than a year old - one petrol, one diesel - both of which brag about efficiency and use the latest tech. But it's the diesel that gets closer (much closer) to the official figures than the petrol could ever hope to and in all driving conditions.

Sorry to disappoint all the VAG haters on here but the A6 ultra can really get some big economy numbers without trying too hard, witness the recent record it broke. My Focus ecoboost does OK the motorway but in mixed driving it's hopeless, just boost and no eco.

fadyady 16 June 2015

The bold new Mazda

I like Mazda. No. I don't have or drive one. But I like Mazda for having the balls while every other car maker in the world follows the road laid out 15 years ago by the Toyota with its Prius.
michael knight 16 June 2015


Wow...all these online armchair development engineers! Miserable naysayers.
Do you really think a company makes these claims without having done years, yes years of development?
Christ on a bike.
scotty5 16 June 2015

Armchair Marketing expert.

Armchair development engineers - I like it. Well I can change a tyre so I'm not qualified to comment on the engineering proficiency of the internal combustion engine but I do have experience of buying and running a variety of cars over many years and I'll say Mazda is talking bollocks (my engineering terminology). I currently own two cars with a list of fuel saving devices as long as your arm, neither car comes near to achieving the mpg figures of their direct predecessors. Explain that. And when looking for a cheap to run family petrol saloon in 1995 after having been used to a company diesel for three years, I bought a 1.6 Toyota Carina E. Average mpg was around 43mpg. 20 years later, whats the real-world mpg from a smaller 1.0 3 cylinder award winning Ecoboost Focus that replaced their 1.6 that struggled to see 40mpg? Worse than that 20 year old Carina! There's no doubt technology has brought us cleaner and more efficient / powerful engines, but when claims are made they bring more 50% more mpg... I'd hazard a guess the information is coming from Mazda sales and marketing rather than their engineering development dept.
winniethewoo 16 June 2015

michael knight wrote: Wow..

michael knight wrote:

Wow...all these online armchair development engineers! Miserable naysayers.
Do you really think a company makes these claims without having done years, yes years of development?
Christ on a bike.

I think we would all be more believing if other manufacturers made similar claims. For instance, VW, who show innovation through their products like the XL1 and E Golf are aiming by 2020 to have a fleet average of 95g/km across its range as per EU directives. It is finding even this difficult. For a much smaller firm with a much smaller R&D budget like Mazda who has shown no technologically experimental vehicles, nor even has a hybrid in its line up, for them to blow VW out of the water with 60% efficient petrol engines. Please. Its like the new college grad who huffs and puffs about being an entreprenerial millionaire by the time they are 30, the evidence being the 2:2 they got on their business degree.