Alfa Romeo 4C - full technical details

The engineering spec is a long roster of lightweight materials. The sheet moulding compound (SMC) composite used in the body is a special lightweight formulation. Even the glass has been pared down to keep weight low.

Many aspects of the 4C are simple. The steering is unassisted, saving the weight of hydraulics, and the electrical system is relatively simple, featuring fewer than 10 ECUs. The manual air-con, for example, was chosen partly because it doesn’t need an ECU and keeps the engineering lightweight.

Alfa has confirmed that the first UK cars will arrive in late August, with customers of the first, higher-spec Launch Edition models possibly 
taking delivery in September.

Engine


Alfa is at pains to point out that the 4C will be powered solely by a four-cylinder engine mated to a dual-clutch automatic gearbox. Rumours persist, however, that a V6 will come eventually. ìThe four-cylinder is perfect because it gives us the performance of a six but is much lighter, says European sales boss Louis-Carl Vignon. Emissions are better, and in many European markets that is becoming more important, even for sports cars, for 
tax reasons.

The 237bhp, 1.7-litre turbo engine is a lightweight version of the 1750TB engine in the Giulietta, with an alloy block in place of iron, which saves 65kg. Project engineer Domenico Bagnasco says the dual-clutch automatic gearbox 
has been retuned for sharper responses.

Suspension

The suspension is steel wishbones at the front and alloy struts at the rear. The front suspension is bolted directly to the carbonfibre tub, rather than hung off the front subframe. To ensure dimensional accuracy for the suspension set-up, the mounting faces are machined to an accuracy of microns. The front subframe supports the body and radiator and doubles 
as the crash structure, which crumples to protect the tub from damage. 

Project engineer Domenico Bagnasco says the rear strut design is different from typical practice, with lower mounting points internally for the damper units and lower spring mounts to get the package height down in the low-slung 4C. Struts are also used at the back on the Porsche Boxster and were fitted to the fabled Lancia Delta Integrale.

Carbonfibre tub 


The 4C’s carbonfibre chassis will have the highest production volume of any to date, with output planned at a maximum of 16 per day. That’s about 3500 a year. Supplied by Adler Plastics, an Italian carbonfibre specialist based near Naples, it’s the firm’s first road car tub. Adler normally makes racing and aerospace parts and, for Maserati, carbonfibre trim. The tub uses ‘pre-preg’ carbonfibre, which is hand-laid in a one-piece mould and oven cured in vacuum bags. It takes 90 man hours to create. Although this display tub has an all-over polished finish, production cars are polished only where carbonfibre is visible — on the inner sills and central structural backbone.

Body production line

A new building has been converted at Modena to fit out the carbonfibre tub with sub-components and clothe the structure in composite body panels. Panels are painted off-site at a Modena specialist that also sprays Maserati’s special body colours. There are 864 components in each 4C, 136 of them in the main tub/subframe/body structure.