The Ferrari SF90 Stradale the new series-production supercar

From Ferrari Press Release

Ferrari introduces a new chapter in its history with the introduction of its first series production PHEV (Plug-in Hybrid Electric Vehicle), the SF90 Stradale, images, videos and information on which can be seen on the dedicated web site: SF90stradale.com. The new model is extreme on every level and represents a true paradigm shift, because it delivers unprecedented performance for a production car.  Figures such as 1,000 cv, and a weight-to-power ratio of 1.57 kg/cv, and 390 kg of downforce at 250 km/h not only put the SF90 Stradale at the top of its segment, but also mean that a V8 is the top-of-the-range model for the first time in the marque’s history.

The car’s name encapsulates the true significance of all that has been achieved in terms of performance. The reference to the 90th anniversary of the foundation of Scuderia Ferrari underscores the strong link that has always existed between Ferrari’s track and road cars. A brilliant encapsulation of the most advanced technologies developed in Maranello, the SF90 Stradale is also the perfect demonstration of how Ferrari immediately transitions the knowledge and skills it acquires in competition to its production cars.  

The SF90 Stradale has a 90° V8 turbo engine capable of delivering 780 cv, the highest power output of any 8-cylinder in Ferrari history. The remaining 220 cv is delivered by three electric motors, one at the rear, known as the MGUK (Motor Generator Unit, Kinetic) due to its derivation from the Formula 1 application, located between the engine and the new 8-speed dual-clutch transmission on the rear axle, and two on the front axle. This sophisticated system does not, however, make for a more complicated driving experience. Quite the opposite, in fact: the driver simply has to select one of the four power unit modes, and then just concentrate on driving. The sophisticated control logic takes care of the rest, managing the flow of power between the V8, the electric motors and the batteries.  

The SF90 Stradale is also the first Ferrari sports car to be equipped with 4WD, a step necessary to allow the incredible power unleashed by the hybrid powertrain to be fully exploited, ensuring the car has become the new benchmark for standing starts: 0-100km/h in 2.5 sec and 0-200km/h in just 6.7 seconds.

Ferrari’s engineers were able to further broaden the spectrum of dynamic controls by introducing the full-electric front axle, known as the RAC-e (electronic cornering set-up regulator). As well as exclusively providing propulsion in electric drive, the two front motors independently control the torque delivered to the two wheels, extending the concept of Torque Vectoring. Fully integrated into the car’s vehicle dynamics controls, the RAC-e governs the distribution of torque, making driving on the limit much simpler and easier.

The introduction of this hybrid architecture was a challenge with regard to managing the additional weight which was resolved by an obsessive attention to detail and the overall optimisation of the whole of the car. For maximum performance in terms of overall weight, rigidity and centre of gravity, the chassis and bodyshell of the SF90 Stradale is all new, built using multi-material technology, including, for example, carbon fibre.

The development of a hybrid car of this kind demanded the development of a series of innovative aerodynamic solutions. The significant boost in the power unit’s performance brought with it an increase in the amount of heat energy to be dissipated and required the development team to carry out an in-depth review of the aerodynamic flows on the radiating masses. It also demanded new solutions to increase downforce efficiently and guarantee maximum stability at all speeds and in all driving conditions.

Particularly noteworthy is the innovative shut-off Gurney, a patented active system located at the rear of the car which regulates the air flow over the upper body, reducing drag at high speeds with low lateral dynamics loads and increasing downforce in corners, under braking and during changes of direction. 

The new car is epoch-changing from a stylistic perspective as it completely rewrites the mid-rear-engined sports berlinetta proportions introduced on the 360 Modena twenty years ago, instead taking its inspiration from Ferrari’s recent supercars. A good example is the cockpit, which has a smaller frontal section and is placed closer to the front of the car to reduce drag. This was also achieved without impacting on-board comfort.

The track-derived “eyes on the road, hands on the wheel” philosophy takes on a truly central role for the first time too, significantly influencing the ergonomics and styling of the interior. The result is an HMI (Human-Machine Interface) and interior layout concept that are a complete departure from previous models.

Another major innovation is the steering wheel which now has a touchpad and a series of haptic buttons that allow the driver to control virtually every aspect of the car using just their thumbs. The central instrument cluster is now entirely digital with the first automotive application of a 16” curved HD screen which can be fully configured and controlled using the controls on the steering wheel.   

On the central tunnel, improved ergonomics have been combined with an element from the past: the automatic gearbox controls are now selected by a grille-style feature that references Ferrari’s legendary manual gear-shift gate. Thus past and present skilfully merge to point the new Ferrari towards the future. 

The SF90 Stradale also sees the debut of the new ignition key with full keyless technology which will gradually be introduced across the rest of the range, personalised with the model’s name. Thanks to a special compartment in the central tunnel, it becomes an integral part of the car’s styling.

In addition to the sporty version, which references the shape and colour of the signature rectangular Prancing badge sported by Ferrari’s road cars, there will also be a more elegant metal-coloured version.

For the first time on a Ferrari, clients can choose between the standard car and a version with a more sports-oriented specification. The Assetto Fiorano specification includes significant upgrades, including special GT racing-derived Multimatic shock absorbers,   extra lightweight features made from high-performance materials such as carbon-fibre (door panels, underbody) and titanium (springs, entire exhaust line), resulting in a weight-saving of 30 kg. Another difference is the high downforce carbon-fibre rear spoiler which generates 390 kg of downforce at 250 km/h. The Assetto Fiorano includes Michelin Pilot Sport Cup2 tyres designed specifically to improve performance on the track in the dry. They feature a softer compound and fewer grooves than the tyres provided as standard.

The SF90 Stradale is the first ever Ferrari to feature PHEV (Plug-in Hybrid Electric Vehicle) architecture which sees the internal combustion engine integrated with three electric motors, two of which are independent and located on the front axle, with the third at the rear between the engine and the gearbox.  

The internal combustion engine and the electric motors work in synergy to unleash an incredible 1,000 cv which means the SF90 Stradale sets a whole new benchmark in terms of its performance and innovative content not just with regard to the Ferrari range, but also its competitors. 

INTERNAL COMBUSTION ENGINE
Thanks to its 780-cv power output, the turbo V8 featured in the SF90 Stradale raises the bar for the performance limits achievable by this type of architecture. The starting point was the F154 family engine which has won the International Engine of the Year award for the fourth consecutive year, an unprecedented achievement for any power unit.

Together with its 195 cv/l specific power output, which is the highest in the segment, the engine also delivers 800 Nm of torque at 6,000 rpm. To deliver this extraordinary result, Ferrari’s engineers focused on several different areas of the engine, starting by increasing its capacity from 3,902 cc to 3,990 cc  thanks to a larger bore of 88 mm.
The intake and exhaust system was completely redesigned and now features a new, narrower cylinder head with a central injector and the adoption of 350-bar GDI, another first for a Ferrari V8.  

To improve the internal fluid dynamics, not only was a larger diameter intake valve adopted but the ducts are all horizontally lined up at engine head height; the turbo charger assembly has been lowered while the exhaust line is higher, as testified by the fact that the tail pipes are now in the upper section of the rear bumper. The turbos are now equipped with electronically-controlled wastegates to improve catalyser heating and new compressor volutes to optimise fluid-dynamics.

The re-engineering goes well beyond fluid-dynamics: the rationalisation of the layout has resulted in both a lower centre of gravity, thanks in part to the adoption of a smaller-diameter fly wheel, and a reduction in overall weight thanks to the use of Inconel instead of steel for the exhaust manifold. Meticulous attention was lavished on sound quality when redesigning the exhaust system and the result is fuller, richer harmonics across the entire frequency range.  

GEARBOX
The SF90 Stradale sports a completely redesigned 8-speed, oil-bath, dual-clutch transmission. New gear ratios and improved transmission efficiency yield a significant reduction in fuel consumption in urban and motorway driving (-8% in the WLTP cycle) without having to compromise on performance. In fact, there is even a 1% improvement in efficiency on the track. 

An optimised layout, achieved through the adoption of a dry sump and a significantly more compact clutch assembly with a 20% smaller exterior diameter than the current gearbox, has shaved 15 mm off the installed height in the car which, in turn, lowers the centre of gravity of the running gear by the same amount.  

Despite the addition of an eighth gear and a maximum torque boost to 900 Nm (the latter an increase of 20% on the current 7-speed), the gearbox’s overall weight is actually 7 kg lower. That figure rises to 10 kg when the elimination of the reverse gear – now incorporated in the function of the front electric motors - is included.

The new clutch’s performance is 35% higher, transmitting up to 1200 Nm in dynamic torque in gear shifts. Thanks to new-generation actuation hydraulics, total clutch fill times have been cut to 200 ms compared to the 488 Pista’s 300 ms.  

ELECTRIC MOTORS
The SF90 Stradale is equipped with three electric motors capable of generating a total of 220 cv (162 kW). A high performance Li-ion battery provides power to all three motors and guarantees a 25-kilometre range in all-electric eDrive mode, using just the front axle. When the internal combustion engine is turned off, the two independent front motors deliver a maximum speed of 135 km/h with longitudinal acceleration of ≤0.4 g. Reverse can only be used in eDrive mode which means the car can be manoeuvred at low speeds without using the V8. The front motors are integrated into the launch control strategy for maximum performance when accelerating.

FUNCTION MODES
The internal combustion engine and electric motors work in synergy to generate an incredible 1,000 cv, which puts the SF90 Stradale at the very top of the range in performance terms. The control logic optimally manages the power flows either with the emphasis on efficiency or performance depending on the user profile selected by the driver.  

Thanks to an additional steering wheel-mounted selector, dubbed the eManettino (analogous to the Manettino which is used to set the electronic vehicle dynamics modes), the driver can choose from four different power unit management modes:  
eDrive: the internal combustion engine remains off and traction is entrusted entirely to the electric front axle. Starting with a fully charged battery, the car can cover up to 25 km in this mode. This mode is ideal for city centre driving or any other situation in which the driver wishes to eliminate the sound of the Ferrari V8.
Hybrid: this is the default setting when the car is turned on, in which the power flows are managed to optimise the overall efficiency of the system. The control logic autonomously decides whether to keep the internal combustion engine running or turn it off. If it is on, the internal combustion engine can run at maximum power thus guaranteeing powerful performance whenever the driver requires.
Performance: unlike ‘Hybrid’, this mode keeps the ICE running because the priority is more on charging the battery than on efficiency. This guarantees that power is instantly and fully available when required. This mode is best suited to situations in which driving pleasure and fun behind the wheel are the main focus.   
Qualify: this mode allows the system to achieve maximum power output by allowing the electric motors to work at their maximum potential (162kW). The control logic prioritises performance over battery charging.

VEHICLE DYNAMICS
The exceptional work done to boost the power unit’s power would have all been in vain without in-depth dynamics research and the development of a whole series of solutions to boost the SF90 Stradale’s lap times, whilst simultaneously guaranteeing that drivers of all kinds could make full use of the car’s potential and have fun behind the wheel.  

The new hybrid architecture required extensive and lengthy integration work on the car’s many different control logics. The three areas concerned are: the high-voltage system controls (battery, RAC-e, MGUK, inverter), engine and gearbox control and vehicle dynamics controls (traction, braking, Torque Vectoring).

Integrating these areas with the existing vehicle control logics led to the development of the new eSSC (electronic Side Slip Control) vehicle control system. The eSSC introduces three innovative dynamic regulation and distribution strategies for engine torque to all four wheels:
> Electric Traction Control (eTC): optimally manages the availability of the torque – both ICE and electric - distributing it to the individual wheels to suit driving conditions and grip requirements
> brake-by-wire control with ABS/EBD: allows the braking torque to be split between the hydraulic system and the electric motors (brake torque blending), allowing regenerative recovery under braking which actually boosts performance and brake feel rather than compromising them
> Torque Vectoring: available on the front axle to manage electric traction on outside and inside wheel in cornering to maximise traction exiting the corner and help ensure easy, confident, high-performance driving.

Ferrari’s unparalleled quality standards and increasing focus on client service underpin the extended seven-year maintenance programme offered with the SF90 Stradale. Available across the entire Ferrari range, the programme covers all regular maintenance for the first seven years of the car’s life. This scheduled maintenance is an exclusive service that allows clients the certainty that their car is being kept at peak performance and safety over the years. This very special service is also available to owners buying pre-owned Ferraris. 

Regular maintenance (at intervals of either 20,000 km or once a year with no mileage restrictions), original spares and meticulous checks by staff trained directly at the Ferrari Training Centre in Maranello using the most modern diagnostic tools are just some of the advantages of the Genuine Maintenance Programme.

The service is available on all markets worldwide and from all Dealerships in the Official Dealership Network. 

The Genuine Maintenance programme further extends the range of after-sales services offered by Ferrari to satisfy clients wishing to preserve the performance and excellence that are the signatures of all cars built at the factory in Maranello which has always been synonymous with leading-edge technology and sportiness.

Specification link here. Ferrari SF90 Stradale spec.pdf
Video link here. Ferrari_SF90_Stradale_16x9.mp4