In creating the Alfa Romeo 4C, the company wanted to create an affordable exotic car and spiritual successor of the legendary 33 Stradale. To achieve a very high level of performance yet stay within the targeted price range, Alfa Romeo turned to the use of lightweight materials which were previously used only for military and aerospace applications. This keeps the weight of the car low and subsequently allowed the use of a lightweight and powerful four cylinder engine that guarantees excellent performance due to a high power to weight ratio. The fact that the engine is an off the shelf unit helps keep the car within the required budget.

The net results are a car that has a dry weight of approximately 1973 lbs in Europe and has a power to weight ratio of 8.22 lb/hp. In the US, the Alfa Romeo 4C will gain some 342 lbs, due to structural and equipment changes. Below we'll take a look at the chassis of the Alfa Romeo 4C along with some of the differences between the US and European model, with the help of Fiat Chrysler Automobiles and Alfa Romeo.

Applications of composite materials for manufacturing vehicle chassis have so far been limited to supercars costing at least $200,000, or vehicles with very limited road use.

The Alfa Romeo 4C is the first sports car made with extensive use of composite materials like carbon fiber and offered at the price of a mid-sized luxury sedan.

The engineers and designers of the Alfa Romeo 4C had to face many challenges:
• High cost of materials
• Difficulty mass production application
• High design complexity

Achieving these goals allowed the engineers to obtain two main advantages: a high level of integration between components (a single complex carbon part instead of many welded or bolted steel parts) and a considerable reduction of weight.

To understand the benefits provided by the use of carbon it is useful to compare this material with "conventional" alloys and metals.

The 4C is not only the first sports car in its class to offer a carbon fiber chassis, it also spearheaded improved production methods of a wide range of components that had been difficult to apply to mass production, due to the conventional use of pressed steel.

The Alfa Romeo 4C chassis is dominated by the central carbon fiber "tub", which houses the passenger compartment and includes the attachment points of the front suspension.

A strong high resistance steel roll-bar is positioned behind the passengers. This prevents passenger compartment deformation in the event of roll over. There are aluminium structures at both ends that protect against impacts, the rear aluminium structure creates a "cradle" for the engine and transmission, and includes the attachments of the rear suspension. These structures feature controlled collapsibility for safety.

To comply with US crash standards, both the front and rear aluminium structures and the aluminium tub have significant differences on the versions sold in the US market compared to the European versions.

The differences in the European and US versions of the front chassis are indicated below. (front view)

There are also differences between the European and US versions of the aluminium front chassis. The various colors indicate
the different characteristics of the US and European chassis.
• Parts in red: specific parts added.
• Parts in blue: parts in common but different thickness.
• Parts in yellow: same volume but different thickness.
• Parts in grey: parts in common

The following, on the other hand, are the differences relating to the European and US versions of the rear chassis.