Ferrari 308 Structure

The first 308 GTBs were bodied in fiberglass over their oval-section tube frame chassis. The front hood was made of aluminum. The chassis gained further strength from square and round section tubes supporting ancillary components and providing rigidity. Inner floorpans, wheel arches and the front firewall were also formed from fiberglass, with most of the remainder of the car being steel. The seam by the windshield helps identify the rare fibreglass bodied 308 GTB, as do fibreglass edges an and aluminum heatshield. To speed construction, Ferrari began to build the bodies from steel in 1976, though some European examples were fabricated from fiberglass into 1977. Steel increased the weight by 250lbs, with inner wheel arches and floorpan continuing to be formed from glass to retard corrosion. The front hood was always beaten aluminum; the rear firewall and trunk sections were always pressed steel.

The 308 saw its greatest structural change with the introduction of the GTS model. Apart from designing and including the removable fiberglass roof section, the body was strengthened with a roll hoop extending through the B pillars and the roof. Along with the tube frame chassis this ensured that the open car retained rigidity.