The first hybrid car with a folding hard top (RHT) in the Ferrari line-up is able to enhance the emotions of driving en plein air like no other
The SF90 Spider, a convertible version of the SF90 Stradale, has been unveiled during a dedicated digital event that allowed Ferraristas from all over the world to preview a series of exclusive contents concerning the car and some details of its development.
The SF90 Spider, the Prancing Horse’s first series PHEV spider, sets itself as a new benchmark in terms of performance and innovation compared to the range of the Maranello-based company and the production of the entire automotive sector. The car inherits from the SF90 Stradale its extreme range supercar setting and its record-breaking performance, managing to increase driving pleasure and usability thanks to the latest version of the RHT folding hardtop. The SF90 Spider is therefore the ideal car for all those who aspire to the highest level of Ferrari technology without sacrificing the versatility and driving emotions en plein air guaranteed by the RHT architecture.
The SF90 Spider is also equipped with a retractable RHT (Retractable Hard Top) hard top, a solution that allows excellent thermal and acoustic insulation in the covered configuration, no deformation at high speeds and maximum habitability thanks to the double curvature. The roof opens and closes in just 14 seconds even when the car is running thanks to the compactness, simplicity and lightness of the system. The key to the success of the RHT Ferrari, introduced in 2011 on the 458 Spider and constantly evolved since then, was the raising of the separation line between the car body and the roof; the volume occupied by the latter is thus limited to only 100 liters compared to the traditional 150-200. The use of aluminum allowed a saving of about 40 kg compared to traditional rigid roof solutions.
Like the SF90 Stradale, the SF90 Spider also offers an additional set-up available on request for those who intend to take the racing approach to the extreme. The Assetto Fiorano differs from the standard set-up for a series of exclusive contents, including Multimatic shock absorbers derived from the experience of the Prancing Horse in GT competitions with adjustment optimized for use on the track; use of high-performance materials (such as carbon fiber and titanium) that lighten the car by 21 kg; rear spoiler in carbon fiber; Michelin Pilot Sport Cup 2 tires approved for road use and designed to improve track performance in dry asphalt conditions, featuring a softer compound and fewer grooves;
For the first time on a Ferrari spider of the range, the SF90 Spider offers a plug-in hybrid architecture in which the internal combustion engine is integrated with two electric motors at the front, which make up the RAC-e system (Electric Curve Trim Regulator) , and one at the rear, deriving from the experience gained by the Prancing Horse in Formula 1 and which inherits the name MGUK (Motor Generator Unit, Kinetic). The synergy between internal combustion engine and electric motors makes it possible to reach the maximum power of 1000 hp and to position the SF90 Spider at the top not only of the range of the Maranello company, but of the entire category.
The powertrain architecture is defined by a V8 turbo internal combustion engine, by the 8-speed DCT gearbox with Ediff, by the RAC-e electric front axle equipped with two independent electric machines that also performs the function of exclusive propulsion in electric gear, by MGUK electric machine positioned between engine and gearbox, with high-voltage battery and power electronics (inverter) for the management of electric motors.
Thanks to its 780 hp (and 195 hp / l of specific power), the heat engine of the SF90 Spider exceeds any other turbo V8 ever made by Ferrari by 60 hp. To achieve this result, the Maranello engineers concentrated on redesigning the intake and exhaust system. In order to improve the internal fluid dynamics, all the ducts were almost horizontally aligned at the height of the engine heads, the turbocharger unit was lowered and the exhaust line was raised higher. This rationalization has led, among other things, to the lowering of the center of gravity and the containment of the overall weight, also thanks to the use of Inconel® for the exhaust pipe.
The new gearbox with double clutch architecture in oil bath, launched on the SF90 Stradale, has 8 gears. The optimization of the layout, due to the adoption of a dry sump and to the compacting of the clutch unit by 20% compared to the 7-speed gearbox, has made it possible to reduce the installation height in the car by 15 mm with relative lowering of the mechanical center of gravity . Despite the additional ratio and the maximum torque limit of 900 Nm (20% higher than the 7-speed) it was possible to reduce the weight by 10 kg compared to the 7-speed gearbox. The clutch improves performance by 35% compared to the previous application and transmits maximum dynamic shifting torque of 1200 Nm.
In the redesign of the exhaust system, great attention was paid to the sound of the engine, one of the fundamental ingredients of driving pleasure for every Ferrari. Thanks to the introduction of the hot tube system that allows a better transfer of sound inside the passenger compartment, it has been possible to expand the range of frequencies and engine orders, improving on-board sound quality and intensity with increasing rpm compared to the previous ones. V8 Ferrari.
The main energy flows of the hybrid system of the SF90 Spider can be divided into two macro-areas:
1. Delivery, based on the driver’s pressure on the accelerator pedal. The delivery is processed by the engine control and hybrid control systems and is constantly monitored by the electronic control systems. Its modalities can be divided into:
– Electric drive entrusted only to the front axle (FWD mode)
– Hybrid running entrusted to the thermal engine and MGUK (RWD configuration)
– 4WD hybrid gear where the electric front axle is activated on demand by the controller for traction out of corners and energy recovery under braking
2. Recovery, managed by the controller of the hybrid system using three strategies:
- Regenerative braking, available on both axles in both standard braking conditions and in the presence of ABS
- Recovery in release (overbraking) on both axles in conditions of release of the accelerator pedal, managed independently on the front wheels
- Battery charging by managing the operating point of the heat engine and rear electric motor (MGUK)
Under normal braking conditions, priority is given to energy recovery through the use of electric motors: the hydraulic braking system intervenes to support the electric one in the event of sudden deceleration. At high speeds (and high gears) the joint contribution of electric machines, in conditions of high grip, contributes to the reduction of the reaction times of the thermal engine, thus significantly improving longitudinal acceleration and, consequently, the overall performance of the car. .
Given the fundamental role of the management of the hybrid system in the driving experience of the SF90 Spider, the traditional Manettino is flanked by a selector for the management of energy flows called eManettino, it manages the power flows to and from the battery and the traction. There are four selectable modes:
- eDrive: the thermal engine is off and traction is entrusted to the electric front axle; in this mode, it is possible to travel up to 25 km with a fully charged battery (7.9 kWh), which is ideal for urban driving or situations where the roar of the Ferrari V8 can be a problem; the speed limiter at 135 km / h allows the vehicle to be fully used even on extra-urban routes
- Hybrid: mode aimed at optimizing the efficiency of the system. It is the control logic that autonomously decides whether to turn the heat engine on or off, which if turned on can work at maximum power ensuring high performance. The power of the electric motors is limited to reduce battery consumption
- Performance: the heat engine is always kept on and battery charge maintenance is preferred over efficiency, so as to ensure full availability of power; also in this case the electric power is limited to reduce battery consumption. This mode is ideal for any situation where you want to favor fun-to-drive
- Qualify: it allows the 1000 hp maximum power of the system to be reached, as the electric motors are also allowed to work at their maximum power. The control logic favors obtaining maximum performance over maintaining battery charge
In order to make the most of the powertrain capabilities of the SF90 Spider, the engineers have developed a vehicle dynamics system capable of guaranteeing improvements not only in terms of pure performance, lap time, full usability and fun-to-drive for drivers. of each level. The hybrid architecture required precise integration between the numerous control logics present in the car, including that relating to the high-voltage electrical system (battery, RAC-e, MGUK, inverter), that of the powertrain and the electronic controls of the vehicle (traction, braking, Torque Vectoring).
All these logics have been enclosed in a single vehicle dynamics control system called eSSC (electronic Side Slip Control), the main innovations of which can be summarized in three innovative strategies for adjusting and dynamic distribution of the drive and braking torque on the wheels:
– Electronic Traction Control (eTC): manages and optimizes the availability of driving torque by distributing it on the individual wheels according to the driving conditions
– Torque Vectoring: manages electric traction when cornering on the outer and inner wheel of the front axle, in order to maximize traction at the exit and make it easier to drive at the limit
– Brake-by-wire control with ABS / EBD: divides the braking torque between the hydraulic system and electric motors, allowing regenerative recovery under braking, improving performance and feeling
The introduction of the hybrid architecture also entailed a challenge from the point of view of weight management: although the additional 270 kg of the hybrid system were amply compensated by the surplus of power delivered (220 hp, with a weight / power ratio of the system equal to at 1.23 kg / hp), a great deal of optimization and lightening of the vehicle was necessary to reduce its weight to 1670 kg and thus guarantee a record weight / power ratio, equal to 1.67 kg / hp; the perception of weight while driving is further mitigated by the RAC-e electric front axle which, by considerably improving traction and cornering stability, facilitates reaching the limit and provides an equivalent lightening quantifiable in about 200 kg.
The chassis has been completely redesigned to withstand the stresses deriving from the new power unit and the introduction of four-wheel drive. Thanks to the introduction of innovative technologies and contents, such as the bulkhead between the cabin and the engine completely in carbon, the torsional stiffness of the SF90 Spider frame is increased by 30% compared to the previous platforms without penalizing the weight, to the full advantage of the dynamic qualities of the car.
Just as the SF90 Stradale has been able to redefine the level of aerodynamic performance of the Ferrari range, the SF90 Spider has managed to push the limit even further. The main aerodynamic development objectives were the maintenance, with the roof closed, of the aerodynamic performance level of the SF90 Stradale; the minimization of turbulence and aerodynamic noise with open roof; and the optimization of flows in the engine compartment.
The synergy between Aerodynamics and Centro Stile has made it possible to achieve values of load and efficiency at the top of the category using innovative solutions in the pure Ferrari spirit, that is, seeking the best expression of sportiness in the sculpture of forms. The main contents of the aerodynamic design of the SF90 Spider include the Gurney shut-off (patented active system that varies the vertical load on the rear), the vortex generators on the front floor and the new forged wheels with airfoil and blown geometry. The results in terms of performance are impressive: the vertical load generated in curves at 250 km / h is equal to 390 kg in the special Assetto Fiorano set-up.
To allow the driver of the SF90 Spider to benefit from its 1000 hp efficiently and without compromising the aerodynamic coefficients, it was essential to pay attention to the management of the cooling flows of the engine, gearbox, turbocharged air, battery pack, electric motors, inverters, systems. charging and braking system.
In the engine compartment, for example, there are thermal elements that develop temperatures close to 900 ° C and electronic components with very stringent thermal specifications. The presence of the hood housing tank drastically changes the management of heat flows in the engine compartment: it is important that the hot flow directed upwards is evacuated correctly and that the path followed by the hot flows does not interfere with the delicate components of the power electronics.
Since the presence of the hood housing tank inhibits the functionality of the vents placed immediately behind the roof of the SF90 Stradale, the rear window of the SF90 Spider is equipped with carefully sized transversal slits that perform the function of a chimney without interfering with the aerodynamics of the car at the high speeds.
The thermal engine and the gearbox are cooled by two radiators placed in front of the front wheels; the flow of hot air coming out of them is directed to the lateral areas of the bottom instead of along the sides, thus allowing better control of the temperature of the air flow entering the air intakes in front of the rear wheels, which increases the efficiency of intercoolers. Electric cars and inverters, on the other hand, are cooled by a separate circuit whose radiator is located at the front and is powered by a socket in the center of the front bumper.
Il circuito di raffreddamento dell’impianto frenante è stato rivisto per soddisfare i requisiti prestazionali della SF90 Spider; per l’anteriore è stata sviluppata una pinza freno con appendice aerodinamica integrata in grado di distribuire in modo efficiente su pastiglie e disco il flusso a elevato contenuto energetico proveniente da una presa d’aria dedicata posta sul paraurti anteriore, subito sotto al faro; i freni posteriori sono ventilati da due prese d’aria sul sottoscocca vicine alle ruote posteriori.
The load level of the SF90 Spider is largely determined by the patented active system placed on the tail and called shut-off Gurney: in order to guarantee the same performance as the SF90 Stradale, it was necessary to work on volumes and surfaces of the roof, so to manage the direction of the aerodynamic flow directed to the rear of the car. The Gurney shut-off consists of a fixed profile at the rear and a movable wedge-shaped profile at the front. The system is controlled by a sophisticated control logic which, by monitoring parameters such as speed, accelerations of the steering wheel angle and pressure on the brake pedal hundreds of times per second, identifies the dynamic conditions in which greater aerodynamic load is desirable and activates the system , which can assume two configurations:
– Low Drag: the two elements are aligned, suspended on the engine hood. The movable wedge forms a perfect aerodynamic fairing for the fixed element, letting the air flow above and below the Gurney shut-off, made almost invisible to the flow
– High Downforce: the mobile element lowers and closes the lower opening that allows the passage of air; the mobile and fixed sections constitute an aerodynamic profile capable of diverting the flow and generating a significant amount of vertical extra-load
The rear load is balanced on the front by a saber-shaped vortex generator system. The contribution of this solution has been taken to the extreme on the SF90 Spider: the front frame is raised by 15 mm with respect to the plane of the central frame at these devices, which allows a greater air flow towards them and an enhancement of their effect. . The bottom of the SF90 Spider is therefore the most deporting ever made by the Maranello company. The diffusers placed in front of the front wheels and the shape of the hood also contribute to generating vertical load on the front axle.
A specific aerodynamic study has been dedicated to the geometry of forged rims, whose construction technology allows greater freedom in the search for aerodynamic solutions. On their external channel there are elements equally spaced between the spokes and modeled as wing profiles, whose geometry allows the rim to function as the propeller of an impeller, increasing the removal of air from the wheel compartment and creating an extractive effect which benefits also the flow passing through the front speakers. Furthermore, the system aligns the flow out of the rim to that flowing along the sides, reducing the deviations given by the air flow outgoing in the direction transversal to the motion and thus decreasing the Cx of the car.
In the cockpit of the SF90 Spider there are two specific aerodynamic elements that guarantee an excellent level of aerodynamic protection for the occupants with the open roof: the blowing of the finish behind the heads of the driver and passenger and the double layer that characterizes the cover of the upper part tunnel. These solutions, practically neutral in terms of increased resistance, guarantee comfort in line with that of other mid-rear-engined Ferrari spiders.
The definition of the external shapes of the SF90 Spider follows the principle that guided the development of the SF90 Stradale, that is, the creation of a futuristic and innovative design that conveyed both the racing attitude of the car and the concept of a range supercar.
With the car closed, the side, front and rear of the SF90 Spider respect the distinctive characteristics of the SF90 Stradale, a non-trivial exercise considering that the architecture provides for the housing of a retractable roof moved by complex levers and that it was imperative to maintain the performance of the stiffness of the frame. The result was achieved by reshaping the surfaces in order to integrate the tonneau cover into the B-pillar of the SF90 Stradale, preserving the style theme. The flying buttresses behind the occupants’ heads, characteristic of every Ferrari spider, are also harmoniously integrated into the body of the car as if they emerge from a structure under the skin.
The result is that, even with the roof off, the proportions of the SF90 Stradale are transferred to the SF90 Spider without formal compromises; this is even more surprising considering that the visibility of the engine through the rear window is not affected by the bulk of the roof. The engine, the real jewel of the car, therefore remains the undisputed protagonist, clearly visible both with the roof closed and en plein air. Viewed from above, to further emphasize the two-seater configuration of the car, the flying buttresses are aligned with the seats with a consequent advantage in rear visibility with the roof stowed.
The cabin and the roof adopt style solutions taken from the SF90 Stradale that allow to maximize aerodynamic penetration and accentuate the sporty temperament without compromising on board comfort. The passenger compartment has been moved forward, the roof is 20 mm lower, the A-pillars are more slender and the windscreen curvature has been increased.
In addition to preserving the silhouette of the SF90 Stradale, the look of the SF90 Spider in an open configuration is extremely dynamic: the absence of the roof produces a lowered effect of the visual center of gravity of the machine, further highlighted by the chromatic detachment of the covers of the bars on which abut the flying buttresses.
The front is dominated by a pronounced nose which helps to highlight the aggressive character of the car; the three front air intakes are dedicated to cooling the electric machines (front) and the endothermic engine (side). The SF90 Spider adopts the Matrix LED technology of the headlights which improves visibility in all conditions thanks to the active control of the light beam.
The rear is dominated by the high exhausts that derive from the optimization of the layout of the exhaust line, whose reference to racing cars is stylistically exploited to enhance the racing nature of the SF90 Spider; the effect is made even more evident by the lowering of the tail. The line of the headlights, with their elongated shape, also represents an element of discontinuity compared to the now classic style with round headlights of the Ferrari mid-rear-engined berlinettas.
The definition of the interior was guided by the redesign of the HMI, which has made a leap forward in epochal proportions since the SF90 Stradale. The on-board instrumentation is almost totally digital and the car is off in black, giving the passenger a minimalist look. By pressing the ‘Engine Start’ button on the steering wheel, a start ceremony involves all the components of the pilot station until the cockpit is switched on.
The central cluster consists of a single 16 ” high definition digital screen, curved towards the driver to facilitate reading and emphasize the enveloping effect. In the default screen, everything is dominated by a large circular tachometer framed by the battery charge indicator, on the sides of which are the navigation screen and the one on the audio controls. The large size of the screen allows great flexibility in customizing the screens, which can be easily navigated using the steering wheel controls. For example, you can view the navigator map in full screen.
Thanks to the introduction of the head-up display, the main information can be projected onto the windshield within the driver’s field of vision, thus allowing him not to distract his attention from driving in compliance with the philosophy Eyes on the road, hands on the wheel that has always guided the development of every Formula 1 Ferrari and which has been gradually transferred to road sports cars.
The steering wheel of the SF90 Spider completes the process of technological transfer from the world of racing by introducing a series of multi-touch controls that allow the driver to control every aspect of the car without ever taking his hands off it. Traditional controls include the iconic Manettino and the control of headlights, windshield wipers and direction indicators. As for the touch controls, the pad on the right spoke allows you to navigate the screens of the central cluster, while on the left spoke the controls for voice commands and cruise control appear. In the central area, at the bottom left, there are the four buttons for selecting the power unit modes.
The F1 bridge, characteristic of the previous models, disappears from the central tunnel and gives way to a modern reinterpretation of the gear selection gate, a true icon of manual gearbox Ferraris. In the new gate, the gear selection grid becomes a digitized grid for automatic transmission control. In the rear part of the tunnel there is the ignition key housing, an exact replica of the horse emblem on the bonnet that becomes a real completion of the interior style. The key works in full keyless mode, so as to allow not only ignition, but also the opening of the doors without being removed from the pocket.
7 YEARS OF MAINTENANCE
Among the main advantages of the Genuine Maintenance program, scheduled checks (at intervals of 20,000 km or once a year with no mileage limits), original spare parts and accurate inspections through the most modern diagnostic tools by qualified personnel trained directly at the Ferrari Training Center in Maranello. The service is available in all markets and concerns all points of sale of the official network.
Thanks to the Genuine Maintenance program, the wide range of after-sales services offered by Ferrari is further expanded to satisfy customers who wish to keep the performance and excellence that distinguish the cars manufactured in Maranello unchanged over time.
Type V8 – 90 ° – turbo – dry sump
Total displacement 3990 cm 3
Bore and stroke 88 mm x 82 mm
Maximum power * 780 hp at 7500 rpm.
Maximum torque 800 Nm at 6000 rpm.
Maximum speed 8000 rpm.
Compression ratio 9.4: 1
Maximum power eDrive 162 kW
Maximum eDrive range 25 km
Battery capacity 7.9 kWh
DIMENSIONS AND WEIGHTS
Length 4704 mm
Width 1973 mm
Height 1191 mm
Wheelbase 2649 mm
Front track 1679 mm
Rear track 1652 mm
Dry weight ** 1670 kg
Dry weight / power 1.67 kg / hp
Weight distribution 45% front / 55% post.
Luggage compartment capacity 74 liters
Fuel tank capacity 68 liters (11 reserve)
TYRES AND RIMS
Front 255/35 ZR 20 J9.5
Rear 315/30 ZR 20 J11.5
Front 398 x 223 x 38 mm
Rear 360 x 233 x 32 mm
TRANSMISSION and EXCHANGE
F1 dual-clutch gearbox and 8-speed, four-wheel drive, electric front axle
Electronic controls: eSSC: E4WD (eTC, eDiff3), SCME-Frs, FDE 2.0, EPS; Performance ABS / EBD with energy recovery
Maximum combined power *** 1000 hp (735 kW)
0-100 km / h 2.5 s
0-200 km / h 7.0 s
100-0 km / h <29.5 m
Maximum speed 340 km / h
Lap time in Fiorano 79.5 s
CO 2 CONSUMPTION AND EMISSIONS – in the approval phase (WLTC cycle)