New details of the next Alfa Romeo Spider have emerged, adding to the considerable excitement circling around the brand’s latest rear-wheel drive-only rebirth. Autocar UK reports that the modern roadster (yet to be unveiled; 2010 Pininfarina 2uettottanta concept shown above) will use a turbocharged MultiAir 1.4 litre engine with upwards of 170 hp.

The new Spider will not have the 4C sports car’s exotic and expensive all-carbonfibre construction, employing a more conventional body structure co-developed alongside Mazda’s next MX-5. Generous use of high-strength steel will keep the weight down to within the region of 1,000-1,100 kg, compared to the 4C’s featherweight 895 kg.

No body panels will be shared between the Spider and MX-5, though plenty of underbody structures will be identical to keep costs down. Each will have its own unique styling and driving characteristics, with the latter underlined by their differing choice of engines – the Mazda will likely stick to a lighter naturally aspirated SkyActiv motor.

It’s said that the two models will only share about 40% of parts (all internal of course), which is significantly lower than typical joint-platform projects where figures upwards of 60% is not uncommon. That’s good to hear, as an Italian roadster with a Japanese feel wouldn’t be ideal, nor is a Japanese one with a heavy Italian flavour.

It’s still early days, but you can expect the next Mazda MX-5 to be unveiled in early 2015, with the Alfa Romeo Spider following suit closer to the year’s end.