Design emphasis for the F355 was placed on significantly improved performance, as well as drivability across a wider range of speeds and in different environments (such a low-speed city traffic.). Apart from the displacement increase from 3.4 to 3.5 L, the major difference between the V8 engine in the 348 and F355 is the introduction of a 5-valve cylinder head. This new head design allowed for better intake permeability and resulted in an engine that was considerably more powerful, producing 380 PS (279 kW; 375 hp).
The frame is a steel monocoque with tubular steel rear sub-frame with front and rear suspensions using independent, unequal-length wishbones, coil springs over gas-filled telescopic shock absorbers with electronic control servos and anti-roll bars. The car allow selection between two damper settings, "Comfort" and "Sport". Ferrari fitted all road-going F355 models with Pirelli tires, size 225/40ZR 18 in front and 265/40 ZR 18 in the rear. Although F355 was equipped with power-assisted steering (intended to improve low-speed drivability relative to the outgoing 348), this could optionally be replaced with a manual steering rack setup by special order.
Aerodynamic design for the car included over 1,300 hours of wind tunnel analysis. The car incorporates a Nolder profile on the upper portion of the tail, and a fairing on the underbody that generates negative lift when the car is at speed.
Source: Wikipedia (original)