The 360 was designed with a Spider variant in mind; since removing the roof of a coupe reduces the torsional rigidity, the 360 was built for strength in other areas. Ferrari designers strengthened the sills, stiffened the front of the floorpan and redesigned the windscreen frame. The rear bulkhead had to be stiffened to cut out engine noise from the cabin. The convertible’s necessary dynamic rigidity is provided by additional side reinforcements and a cross brace in front of the engine. Passenger safety is ensured by a strengthened windscreen frame and roll bars.
The 360 Spider displays a curvilinear waistline. The fairings imply the start of a roof, and stable roll bars are embedded in these elevations. Due to use of light aluminum construction throughout, the Spider weighs in only 60 kg (130 lb) heavier than the coupé.
As with the Modena version, its 3.6 liter V8 with 400 bhp (300 kW) is on display under a glass hood. The engine — confined in space by the convertible’s top’s storage area — acquires additional air supply through especially large side grills. The intake manifolds were moved toward the center of the engine between the air supply conduits in the Spider engine compartment, as opposed to lying apart as with the Modena. In terms of performance, the 0-60 mph time was slightly slower at 4.4 seconds due to the slight weight increase, and the top speed was reduced from 189 to 180 mph (304 to 290 km/h).