Mazda’s next-generation Mazda MX-5 will combine a small-capacity turbocharged four with lightweight engineering to return the two-seater in 2012/13 to its original agile sports car concept.

According to a senior insider, Mazda’s engineers have been tasked with cutting 275kg from the 1075kg ‘empty’ kerb weight (the weight without a driver) of today’s MX-5 to hit an ambitious target of 800kg.

This would be a significant step forward for a volume-production sports car. In its leanest form, the MX-5 weighed just 955kg at its 1989 debut.

That was an era before comparative crash-testing added weight through heavy body structures, side-impact bars and airbags, and extensive, luxury specs became standard.

Autocar’s product planning source doubts that the highly ambitious 800kg target will be met. However, progress is described as “not bad”.

Weight-saving will be fought on many fronts, starting with lightening as many mechanical components as possible, adopting lightweight materials and deleting features to create a more minimalist spec.

This downsizing of components will then lead to a ‘virtuous circle’ in which a lighter car allows a lighter transmission, smaller brakes, less hefty suspension and so on.

In place of today’s 1.8 and 2.0-litre engines, the next MX-5 will use a small direct-injection four-cylinder turbocharged engine of around 1.5 litres. It will feature variable cam phasing, lighter, low-friction reciprocating parts, and possibly a new exhaust manifold design that achieves more effective exhaust gas evacuation.

Many of these developments are part of Mazda’s SkyActiv engineering campaign, which aims to improve the efficiency of every aspect of its cars.