The new two-seat roadster has reached production without any discernible changes from the earlier concept car, unveiled at the 2014 Geneva motor show.
Key among the elements differentiating the 4C Spider from the 4C coupé launched in 2013 is its removable roof. It will initially be available as a soft, stowable canvas arrangement – as hinted at on the concept, although an optional carbonfibre hard-top is set to become available after UK sales begin in mid-2015, according to Alfa officials.
The 4C Spider also receives a carbonfibre panel that covers the rollover bar behind the cabin, unique single-lens headlights and a new range of alloy wheels, which measure 17in in diameter up front and 18in at the rear as standard.
In accommodating the new roof, the drag coefficient has extended from the 0.33 claimed for the 4C to 0.34 for the 4C Spider, although the new roadster looks every bit as striking as its fixed-roofed sibling.
In a move that has kept the weight gain down to just 10kg (at 1128kg) while retaining a level of rigidity described as being similar to that of the 4C coupé, the 4C Spider has a carbonfibre windscreen frame that is bonded and bolted to its carbonfibre monocoque chassis.
The glass for both the windscreen and side windows is described as being 10 per cent thinner than on the 4C.
Additionally, Alfa Romeo has endowed its new model with a newly designed aluminium rollover bar that provides mounting points for the 4C Spider’s unique engine lid, plus a beefed-up strut brace within the engine compartment.
Power comes from the same mid-mounted turbocharged 1.7-litre four-cylinder engine used by the 4C coupé. Running continuously variable valve timing, it delivers 237bhp at 6000rpm, in the process providing the 4C Spider with a power-to-weight ratio of 210bhp per tonne. Torque swells to a peak of 258lb ft of torque between 2100 and 3750rpm.
Alongside the standard and racing exhausts already available on the 4C, the 4C Spider also comes with an optional lightweight Akrapovic exhaust that uses asymmetrical mufflers, a dual-mode valve system with a link pipe to reduce cabin drone and two centre-mounted tailpipes.
Drive is channelled through Alfa Romeo’s six-speed dual-clutch automatic gearbox. It offers the driver the choice of four different driving modes: All Weather, Natural, Dynamic and Race – the latter allowing the engagement of a launch control system for maximum off-the-line acceleration.
Alfa Romeo claims the 4C Spider is capable of accelerating from 0-60mph in just 4.1sec, matching the 4C coupé's time.
In keeping with plans by Alfa Romeo to hold back on detailed information pertaining to the 4C Spider until closer to its introduction in July, no further performance claims have been made public.
The 4C Spider will be assembled alongside the 4C coupé by Alfa Romeo sister company Maserati in Modena, Italy. Production details are yet to be revealed, although officials say volume will be similar to that of the fixed-roof variant at around 3500 units per year.
Similarly, pricing is being kept under wraps. However, indications are the 4C Spider will command a slightly higher price than the £45,000 4C.
Speaking at the unveiling of the 4C Spider, Alfa's US boss, Reid Bigland, said: "After a 20-year absence, what gives us the confidence to return is the strength of our past, present and future. Our commitment to the brand is unprecedented. By the end of 2015 we'll have more than 1000 engineers dedicated solely to Alfa. We are led by two ex-Ferrari managers. We are on track for success.
"Our plans remain on track for eight new Alfas on sale in the States by 2018. Our plans are on track to relaunch in the US."
Alfa Romeo currently has 100 dealers in the US. The brand wants 200 dealers by this time next year.
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