2015 Mazda MX-5 to debut in Chicago

The fourth generation of the Mazda MX-5 is nearing, and is tipped to have dropped weight and grown a longer nose to accommodate more efficient SkyActiv engines. The roadster is being developed on a new platform that will also be shared with the next Alfa Romeo sports car.

Expected to be unveiled at the 2015 Chicago motor show -- 26 years after the first generation debuted there in 1989 -- the new MX-5 will have a lengthened wheelbase and bonnet to house the extra long exhaust manifold of Mazda's efficiency-focused naturally-aspirated 1.5-litre and 2.0-litre Skyactiv mills, with the company having decided not to go down the turbo path for the two-seater, according to Autocar.

Australian specification is a long way from being announced, but at the moment we get a single 2.0-litre engine with the choice of a six-speed manual or six-speed sports auto transmission. Skyactiv technology is predicted to considerably improve the fuel economy, currently 8.1L/100km.

While the longer bonnet -- with the front axle pushed forward -- has a functional basis, it will also contribute to what a Mazda insider told the UK site was the carmaker's "best-looking car ever" with “very clean and simple” lines. “It is such a good-looking car - recognisable as an MX-5, but with very clean styling,” the source is reported as saying.

That means we're unlikely to see the five-corner grille and detailed styling of the rest of the recent Mazda product make its way onto the MX-5, with the nose expected to continue with uncluttered, smooth planes and lower air intakes.

Mazda was previously trying to get the weight down to the 1000kg level, and while that target has been abandoned, you can still expect the coming MX-5 to shave around 70kg off the current car's 1167kg (manual) and 1177 (auto), aiming to be the lightest in its class.

The car will be offered in both soft-top and folding hard-top versions (depending on markets around the world) however Australia currently takes only the hard-top. The good news is that the roof also reportedly is lighter, and has been redesigned to swallow less space in the boot.

This reporter is on Twitter: @KarlaPincott