Ferrari set out to develop the Enzo as an integrated system designed for extreme performance, in which even the limits of the performance achievable by the driver were enhanced, thanks to a man-machine interface typical of Formula 1.
Never before has style been derived so directly from function as in this model. Pininfarina wanted to create an uncompromising car that would break away from the approach used for the GTO, F40 and F50 that preceded it, to develop a new formal language that looked to the future. The engineers tried to create visual links with the world of Formula 1, to which the Ferrari Enzo owes its technology, while highlighting its compactness and lightness. The result is a complex, sculpted form.
In developing the Enzo, Ferrari set itself two pure performance targets which would represent a milestone for ultra-fast cars: to increase the grip limit in medium-fast bends by increasing downforce (lateral dynamics,) while maintaining a very high top speed, over 350 km/h (longitudinal dynamics.) This meant that different aerodynamic configurations with contrasting characteristics had to coexist on the same car. In racing cars, this problem is solved by developing wings and special aerodynamic accessories for each circuit. But in the case of the Enzo, for which the various targets had to coexist in a single aerodynamic configuration, a concept of active, integrated aerodynamics was developed. The high downforce configuration was obtained with a basic aerodynamic set-up developed on the basis of contemporary concepts for the definition of covered-wheel racing cars combined with the expertise of Ferrari Gestione Sportiva.
The optimal aerodynamic set-up is kept stable by special elastic features of the car’s engineering and by active aerodynamic control.
As the speed increases from low-medium to high-very high, the engineering ensures that the car takes on the optimal aerodynamic set-up (maximum downforce obtained with an optimal load distribution) by varying the rigidity on the basis of ground clearance. As the speed climbs even higher, this set-up is maintained by the combined action of the flexible mechanical components and by active control of the spoilers. At very high speeds, the actively controlled spoilers (front and rear fins) limit the maximum vertical load, thus making it possible to keep the car above a set minimum ground clearance. On the Enzo, the aerodynamic load and balance can be modified on the road by means of a pair of flaps positioned in the front slides and a rear spoiler.
Vehicle Control System
The Enzo project is the first example of the complete integration of the vehicle control systems. Engine, gearbox, suspension, ABS/ASR, and aerodynamics all interact to optimise the vehicle’s performance and safety. This presupposes an innovative approach to the design of the control system architecture, and to the development and fine-tuning of the subsystems on the car. It was made possible by the collaboration and specialist skills of Gestione Sportiva, and performance of each system was designed to enhance that of the entire car. The target when defining the control strategies of each subsystem was therefore the optimal behaviour of the car. The subsystems that interact are: the engine, gearbox, suspension, aerodynamics, and the ABS/ASR system. The large number of systems made it necessary to use special sensors. Management of the sensors is divided between the various control systems, each of which shares the relevant information with the rest of the system. The way the systems interact depends on the driving modes that the driver can choose from. The Enzo offers several set-ups: Sport, Race, No ASR.
The architecture of the F140 project was designed to minimize the section of the cables that link the utilities positioned on the steering wheel, the steering column, the onboard instruments, and the rest of the car. To achieve this goal, the architecture was based on a high speed communication line which links several different control units which pick up the signals "in the surrounding environment". These signals are transformed into information which can then only be exchanged through the communication line.
The engine of the Enzo Ferrari (which is known by its project number F140) is a 12-cylinder aspirated unit in a 65° V, a cylinder capacity of 5,998 cc, with a completely new design that draws on experience gained in Formula 1, and has a number of unique technical features. The cylinder head design reveals its Formula 1 origins: the "pentroof-type" combustion chamber, with four valves per cylinder, plus inlet and exhaust ducts designed to maximise the exhaust coefficients and combustion speed.
The cylinder case is built of aluminum with press-fitted sleeves lined with nicasil, with seven main bearings, and sleeve intervals of 104 mm. The con rods are made of titanium, the piston design is new, the crankshaft is lighter and the cylinder heads have four valves with high fluid dynamic efficiency, a new structure to increase rigidity, and a different oil discharge layout.
The timing gear features four overhead camshafts, direct valve control, and hydraulic tappets. It is completely chain-driven, with central transmission on triple gearing. The timing of the inlet and exhaust manifolds is continuously variable, thanks to the intervention of four variable advances activated by the engine control unit throughout the operating range via a high pressure hydraulic system, with the goal of lowering the noise and enhancing versatility.
The lubrication sump is of the F1 wrapround type, incorporating the main bearings and a specific oil recovery circuit to increase efficiency.
The variable geometry inlet manifold is also borrowed from Formula 1, with a system of small telescopic derivation cones, combined on this V12 application, with variable timing gear with a continuously variable advance on the four camshafts and a high pressure control unit.
Electronic engine management is provided on each row of cylinders by a Bosch Motronic ME7 unit which controls the PFI multiple injection system, the drive-by-wire throttle valve, and the single coils on each spark plug. Six knock sensors mounted on the crankcase guarantee knock control.
The performance goals of the new V12 have been met in full, in order to supply a unique blend of very high power, generous torque from low speeds and versatility. In spite of the large capacity of the engine, the applications derived most directly from Ferrari’s Formula 1 experience have made it possible to keep the specific power of the engine at an extremely high 110 bhp/litre.
F1 Transmission and Gearbox
In the F140 project, the rear gearbox is coupled directly to the engine by an element that incorporates the engine oil tank, the bevel gear pair, and the self-locking differential. In line with the car’s performance targets, the gearbox unit was developed only in a Formula 1 version. Gear changes are entrusted entirely to an electrohydraulic system which activates the gearbox and clutch. Gear change control is managed electronically and activated by paddles positioned behind the steering wheel, modifying engine torque and vehicle dynamics.
The project was designed for extremely sporty performance and adopts triple cone synchronisers on all six speeds. Lubrication is forced, with a large pump and lower oil level to minimise losses due to ventilation/shaking. The architecture with three bearings guarantees optimal gear train coupling even at high torque. The twin plate clutch with aluminium housing and a diameter of 215 mm also speeds up engine dynamics and synchronisation.
The number one goal of the Enzo project was to cut gear change times (down to 150 milliseconds) in the interests of extremely sporty use. The F1 gear levers are made of carbon, with an optimised shape and size, and they have been made symmetrical by transferring the direction indicator controls to the steering wheel spokes. The gear change pushbuttons are mounted on the steering wheel, as are the two different gear change modes, Sport and Race, as well as the reverse gear selector button. Each of these modes comes with its own integrated software controlling damping and traction control systems (ASR.)
In RACE mode and with ASR disengaged, the Launch Control strategy borrowed from Formula 1 is also available, allowing the driver to start off at top speed in good grip conditions. The driver keeps the brake pedal down while he uses the accelerator pedal to choose the engine speed at which he wishes to set off. When he releases the brake pedal, the clutch closes rapidly while torque control is left to the driver.
The system fine-tuned by Ferrari for its Formula 1 transmission envisages a special multiple telltale at the centre of the main instrument panel which keeps the driver constantly informed about the state of the system and the speed engaged.
The chassis was built entirely of carbon fibre and aluminium honeycomb sandwich panels, which made it possible to meet demands for outstanding rigidity, lightness and safety. In order to pass the offset collision tests required by the latest safety standards (56 km/h impact), highly sophisticated CAE methodologies were adopted to optimise the composite structures, to identify the optimal bodyshell structure, and to maximise the contribution of the reinforcement skin, where it is needed to support the basic panelling. The final result already meets the stricter future standards which will raise the collision speed to 60 km/h.
Respect for the styling and access targets (door solution with impact on the roof of the chassis) and the goal of passing 64 km/h offset collision tests with a view to further evolution of the requirements (extremely demanding in structural terms as a result of the 30 % increase in kinetic energy to be dissipated compared to previous collision standards), required complex planning of the tooling and the manufacturing methods.
The use of CAE optimisation methodologies was extended to the engine support frame, and particularly to the distribution of thicknesses in the suspension casting. In line with the work done for the bodyshell, a specific analysis set-up made it possible to identify the best weight-performance trade-off, supplying exact indications for the distribution of casting thicknesses.
Experiments confirmed the validity of the solutions chosen: torsional rigidity proved to be higher than the project target and to correspond to the values calculated, while all the homologation collisions gave a positive result from the start.
These results are all the more significant if we consider that the chassis weight had also been decreased considerably to 92 kg (compared to the 102 kg of the composite chassis of the earlier F50).
Suspension and Wheels
The Enzo has independent front and rear suspension with jointed double wishbones, and antidive-antisquat geometries to limit pitching during the transfer of longitudinal loads. The front uspension, which is push-rod in type with an opposed damper, also incorporates a lift to increase ground clearance during parking maneuvers. The rear suspension was designed to adapt to the chassis, with the engine-gearbox-differential assembly supported elastically, and a rear subframe.
Combined with this suspension layout, an adaptive set-up was adopted for the Enzo project, based on a system of continuous control of the damping effect. The adoption of this system on the vehicle makes it possible to reconcile handling requirements (i.e. roadholding, minimal variation of the ground load) with the demands of comfort (movement and acceleration of the "shell", vibration transmitted to the driver), without having to adopt passive solutions (standard dampers) as a compromise.
In other words, electronic adaptation of the damping effect makes it possible to use a damper setting that is sufficiently comfortable in the car’s basic configuration ("Sport" setting), yet there is also a setting that offers extra control in high performance conditions ("Race" setting).
The system uses the unsprung weights (wheels and suspension) to hold the sprung weight still (body) but it also insulates the shell from impulses transmitted to the wheels by the ground. The system is actually made up of four sensors (accelerometers) on the shell, two vertical wheel sensors, one vehicle speed sensor and a brake switch. The dampers are fitted with an internal proportional valve governed by the control unit, allowing damping to be modified instantly.
The braking torque control strategies (via ABS/ASR) were specially developed on the basis of the installed power and the optimisation of the braking system, and achieved a satisfactorily convenient result in terms of torque and braking pressure.
Although the Enzo project put the emphasis on handling, because of the car’s extreme connotations, the adaptive set-up system employed meant that a good level of comfort could be obtained. Where the wheel modules are concerned, single-bolt light aluminium alloy wheels were chosen. The tyres were developed specifically for the Enzo project by Bridgestone and bear the exclusive name "Bridgestone Potenza RE050 Scuderia".
In order to maximise running safety, the car is equipped with a system that measures tyre pressure through special sensors inside the wheel rims, near the inflation valve. These sensors transmit a signal which is picked up by the antennae behind the stone traps on the bodyshell and linked to the control unit of the pressure monitoring system, which transmits the state of the tyre pressure to the instrument panel.
The braking system developed for the car by Brembo features brakes made of carbo-ceramic material (CCM) used for the first time on a Ferrari road car, although Ferrari has been using them for many years on its Formula 1 racing cars. This made it possible to achieve outstanding results on the Enzo for all braking performance parameters. The main benefit required of this application was a decrease in unsprung masses, which was made possible by the significant reduction in the weight of the brake discs (12.5 kg less than conventional brakes). In addition to this, the entire braking system was obviously designed for maximum braking effectiveness and efficiency, in terms of prompt braking, stopping distances, and fade resistance. A further benefit of using brake discs in composite material was achieved in terms of improved reliability over time.
All of the main surfaces are made from unadorned carbon fibre. The functional elements are hooked onto a structural aluminium crossbeam. One of the main goals for the interior of the Enzo was to develop the concept of a facia and steering wheel that could optimise the flow of information and the way controls were activated by the driver, to make the so-called man-machine interface much more efficient.
One element that helped in this direction is the completely new steering wheel, the upper part of which is made of carbon and bevelled so as not to limit external visibility. It contains a series of LEDs which duplicate the telltales and the rev counter, and the lower part has been optimized to make more space for the driver.
Like a Formula 1 steering wheel, it also includes a large number of controls (six) on either side, linked to the main vehicle control functions: vehicle lift, reverse, exclusion/re-engagement ASR, integrated Sport/Race strategy, display configuration.
The control panel is tailor-made for the driver and includes technical features that are easily accessible from the wheel grip, and a compact, mixed analogue-digital instrument panel, in the shape of a reconfigurable graphic screen.
The driver’s seat is an essential part of the driving position structure. A new racing seat was developed, made of carbon fibre and designed to give greater rigidity and to make the driving sensation more precise, filtering even the tiniest flexion in the seat system as much as possible. The aim was to give the Enzo driver the greatest possible awareness of the car’s behavior.
Seat inclination is adjusted by a double Bowden lever system, and includes a lever control on the seat cushion, the only system of its kind in the field of fast sports car seats. The driver can also adjust the squab-seat combination to obtain a perfect driving posture.
Because the project only envisages a version with the F1 gearbox, there are only two pedals (accelerator and brake) which were optimized functionally and stylistically. There are numerous settings, for a total of 16 different configurations.