CHASSIS AND BODY
The Purosangue’s chassis is completely new and was designed from scratch with the aim of producing a
structure of uncompromising rigidity. The lower chassis structure is made entirely from high-strength
aluminium alloy and draws on Ferrari’s enormous experience in the optimal use of these light alloys. Together
with the structural elements of the upper body, it makes up a spaceframe chassis comprised of
closed-section extrusions connected by castings into which load-bearing aluminium sheet metal elements are
integrated.
The chassis is thus lighter than Ferrari’s previous four-seaters’ despite being larger. Improved torsional rigidity
(+30%) and beam stiffness (+25%) figures are both fundamental in improving NVH characteristics and thus
comfort by smoothly and silently absorbing asperities in road surfaces as well as providing an exceptional
feeling of structural integrity.
The extensive use of hollow castings with thin walls – made using internal cores – helped optimise the
structure, maximising performance and guaranteeing improved continuity in the stress lines which, in turn,
guarantees all-important occupant safety requirements. Furthermore, this particular technology improves
assembly quality thanks to more precise integration, fewer components and the consequent reduction in weld
lines.
The bodyshell is made from materials ranging from aluminium to carbon-fibre, with the introduction of
high-strength steel in important areas and flanking the mechanical joins with structural adhesive. Combining
these different materials guaranteed maximum strength where required and also light weight in areas not
subject to stress.
High-strength steel is used for the anti-intrusion bars, the reinforcements on the main nodes and the B-pillar.
Our meticulous attention to detail at the design stage also resulted in the use of different materials within
individual components. One example is the single rear door hinge: the fixed part is an aluminium casting while
the mobile part is constructed from hot-stamped steel.
The single-shell carbon-fibre roof with integrated soundproofing is completely new and delivers rigidity levels
on a par with a glass roof while weighing 20% less than an aluminium roof with soundproofing. From an
ergonomic perspective, we focused on offering as much ingress space as possible whilst still keeping the
wheelbase compact. To do this, we opted for traditional opening for the front doors with a 63-degree opening
(five degrees wider than on our other models) – combined with a brand-new electric, rear-hinged back door
with a 79-degree opening. Aside from referencing the bonnet opening on the Ferrari Monza SP1/SP2 and
other legendary Ferraris from the past, the Purosangue’s front-hinged bonnet also allowed us to craft extreme
forms in the A-pillar area. The gooseneck hinge assembly for the bonnet is made from aluminium for solidity
and stability when being opened.
The aluminium rear hatch is electrically activated: two electric Stabilus tailgate lifters allow it to be opened to
73 degrees for easy access to the boot, and to make loading and unloading even the largest of luggage
simple. The gooseneck hinge assemblies allowed us to craft unconventional aesthetic forms in the upper
spoiler area.
AERODYNAMICS
The very different volumes and constraints of the truly unique Purosangue posed a completely new challenge
for Ferrari’s aerodynamic department, so a radical rethink of both methods and solutions was demanded. The
extremely ambitious drag reduction target, the specific usability and accessibility demands of this particular
model, and the need to cool the imposing V12 and ancillaries demanded hundreds of hours in the wind tunnel
and thousands of CFD (Computational Fluid Dynamics) simulations. The kind of development work dedicated
to the fastest and most powerful sports cars in the range, in fact.
The primary focus of the Purosangue’s aero design was the car’s centreline section, essential to both the air
flow design and to reduce the drag coefficient (Cd), as well as minimising the frontal surface area. The car’s
front silhouette was designed to create the most seamless continuity of profile possible between the area of
maximum curvature of the bonnet and the windscreen header rail. The rear area of the roof, the rear screen
and the spoiler, on the other hand, demanded most work because it is fundamental to managing flow
separations and pressure fields.
The best possible compromise between the need for the smoothest design possible for the roof-rear screen
line and the need to reduce the height of the tail itself was achieved by using two elements that complete the
aero package for the rear of the car: the suspended spoiler and the nolder on the lip of the boot. While the
suspended spoiler helps neutralise the curvature of the roof downstream of the area over the heads of the
rear-seat passengers, the nolder, which is barely 7mm high, channels the wake vortices to create a slight
recompression at the tail of the car.
Moving from the centreline section to the rear volume, a scoop can be seen starting at the rear of the roof and
extending onto the rear screen which creates two crests, one on each side of it. This solution helps to
maintain the headspace required for the rear-seat passengers whilst still correctly separating the flows from
the upper part of the roof and those along the greenhouse area.
Also important to the aero development of the Purosangue was the wake from the wheels: several aero
solutions were implemented to tackle this issue, including integrating louvres into the floating wheelarch trim
front and rear. The most complex system, however, is at the front where both the bumper and louvre work in
synergy to create a powerful air curtain that aerodynamically seals the front wheels, preventing the generation
of transverse turbulence. A duct has been created between the front bumper on the outside of the side air
intakes and the vertical fin. This duct is calibrated to accelerate the flow towards the blown area in the louvre
and create an energised blade of air at an angle to the outer shoulder of the tyre. The outer surface of the
louvre then deflects the flow along the flank.
At the rear of the front wheelarch trim there is a further duct that is profiled to maximise air extraction from
inside the wheel housing. The same solution is adopted on the rear wheelarches with a vent in the rear
wheelarch trim. Its exterior surface has also been profiled to optimise the management of the rear detachment
point of the flow, which runs along the flanks and wheels.
The suspended wing on the bonnet, just ahead of the A-pillar, dubbed the aerobridge in reference to a similar
element introduced on the F12berlinetta, plays a very different role to its namesake. While the latter’s
aerobridge deflected the air flow from the bonnet downwards to boost downforce, the one on the Purosangue
is designed to reduce drag.
The air passing under the wing on the bonnet is energised locally to reduce the negative impact of the vortex
at the base of the windscreen, and to accelerate the flow to increase the amount of air being evacuated from a
vent hidden by the aerobridge, which is part of a complex system of air ducts fed by the intake located over
the headlights. This mass of air is channelled towards the front wheelarch. These flows coming from the front
of the car are naturally vented through the louvres at the top of the front wheel housing, and then continue on
into the engine compartment until they reach the vent under the aerobridge. Similarly, to reduce overpressure
inside the rear wheel housing, a vent has been added just beneath the taillights (in an area of natural suction)
that leads from a duct inside the rear wheelarch.
A blown channel from the lower part of the front bumper towards the underbody reduces the areas naturally
under compression on the front bumper, maximising the quantity of air being channelled towards the
underbody, an element already used on other Ferraris. In this case, however, it is put to a different use: the
energised flow channelled along the underbody by the blown area meets the surfaces of the underbody
specifically designed to generate suction near the evacuation point of the central radiators on the front
underbody. This maximises cooling of the central radiating masses as efficiently as possible and also allowed
the design of a much smaller radiator intake. The Purosangue’s higher ground clearance means that the
exposed area of the wheels makes a significant contribution to drag: as a result, negative ramps were
integrated ahead of the front wheels to maximise the car’s downforce.
The curves of the body’s surfaces were designed to fair in the front wheels and wishbones, thereby limiting the
amount of air entering the wheelarch as much as possible. Pivotal to this effect is a small flap fitted on the
lower suspension wishbone. The low pressure areas that occur naturally behind the front wheels were used to
create two areas of evacuation that boost the efficiency of radiating masses by reducing overpressure in the
engine compartment and reduce drag.
The rear diffuser design is, once again, the result of in-depth optimisation that focused principally on the
synergy between the diffuser itself, the upper body and the rear bumper. The air flow that strikes the diffuser is
gradually expanded and controlled. At the end of this expansion, a subtle nolder detaches the flow after
slightly recompressing it. This boosts the system’s efficiency, simultaneously maximising hot air extraction
from the area around the gearbox and exhaust system compartments.
The Purosangue doesn’t have a rear windscreen wiper, so the rear screen is cleaned by the air flow along the
glass surfaces at the rear. The lower surface of the suspended spoiler is curved to guarantee the air flow is at
the right speed and direct it towards the rear screen. There are two pairs of vortex generators at each end of
the lower surface of the spoiler, which optimise the uniformity of the scrubbing. These counteract the vorticity
naturally caused by the C-pillar, and also work in synergy with the specific shape of the rear screen itself.
The unconventional location of the headlights made it possible to create two air intakes above and below the
DRL. The upper one is used to channel air into the complex blown system which vents underneath the front
aerobridge. The lower one, on the other hand, is used to channel air to the brake cooling system. The design
of the vertical outside surfaces of both air intakes includes an air-catcher which maximises the quantity of air
channelled through them.
Lower down are the intakes for the radiating masses. Seen from the front, the one on the right is the radiator
for the active dampers, which guarantee superb occupant comfort even on very rough surfaces, while the one
on the left feeds air into the radiator for the Power Transfer Unit (PTU) circuit, a torque vectoring electronic
differential. Lastly, the central intake cools both the condenser for the air conditioning circuit, to guarantee
optimally comfortable cabin temperatures, and the iconic, naturally-aspirated V12’s oil and coolant radiators.
VEHICLE DYNAMICS
Development of the Purosangue’s dynamic performance focused on creating a car that was completely
unprecedented on the world stage: a model offering usability and comfort standards that would position it at
the very top of the market as well as delivering signature Ferrari vehicle dynamics and performance on a par
with the rest of the range.
The Purosangue boasts a unique, innovative system that is a world first: Ferrari active suspension technology
enabled by Multimatic’s True Active Spool Valve (TASV) System. Compared to other solutions on the market,
this new suspension architecture offers numerous advantages by combining electric motor actuation with a
high-precision spool valve hydraulic damper into one fully integrated system. The electric motor ensures that
body and wheels can be controlled actively with more force authority and at higher frequencies than traditional
adaptive or semi-active systems.
One advantage of Ferrari’s active suspension system is the speed at which the TASV 48-volt motor actuators
apply force in the direction of the damper’s stroke. The high-power density, three-phase brushless electric
motor was co-developed for this application by Ferrari. The motor uses “slotless” stator winding technology to
minimize radial dimensions and maximize power density. From a mechanical point of view, the motor force is
transmitted in a novel way via a twin-lead ball screw connected directly to the hydraulic damper piston rod
which enables high-frequency response and reduces friction, inertia and package space.
The active suspension system uses accelerometers and position sensors on each suspension corner and
interfaces with the Side Slip Control (SSC) 8.0 and the 6w-CDS sensor. Ferrari’s proprietary control logic,
together with the TASV dampers supplied by Multimatic, electronically manages every performance element
of the fully active suspension system.
This technology optimises maximum cornering performance thanks to the variable and continual distribution of
roll stiffness and the actively lowered roll centre (reduced by up to 10mm), to the benefit of the side force
acting on the tyres and the balance between over and understeer. The high-frequency control regulates both
body motion and wheel movement, thus reducing roll and pitch as well as absorbing road surface
irregularities.
As well as the active suspension technology, the Purosangue is equipped with a new generation front
semi-virtual, high wishbone suspension where the lower wishbone has two attachment points on the hub
carrier. This solution means the virtual lower kingpin attachment point created by the two arms is very close
to the wheel centre, thereby drastically reducing the scrub radius, i.e. the distance between the point of
intersection of the extension of the kingpin axis and the centre of the tyre contact patch at ground level. This
makes the steering wheel less sensitive to road irregularities and braking.
The Purosangue is equipped with the new ABS ‘evo’ controller co-designed with Bosch® and integrated with
the brake-by-wire system that debuted on the 296 GTB. For the Purosangue its function has been further
developed to cope with low grip surfaces and in all Manettino settings, thus optimising performance and
repeatability in all road conditions. This new controller uses information from the Electronic Stability Control
(ESC) to much more precisely estimate the car’s speed in order to determine the slip target for the four
wheels under braking. This improved accuracy means that the longitudinal force of the four tyres can be better
exploited while more accurate estimation also means that repeatability of the manoeuvre around its target
value can be maximised, reducing dispersion due to natural variations caused, for instance, by the condition
of the tarmac.
The EPS-based grip estimation system, originally developed for the 296 GTB, has also been honed for driving
in the snow or on other low-grip surfaces. Using the data in the ECU and the slip angle calculated by the SSC
8.0, the logic can calculate the level of grip between the contact patch of the tyre and the road during steering
inputs. This provides an accurate estimation even when the car is not being driven on the limit, thus making
the self-learning function of grip faster and the grip estimation in all grip conditions more precise.
On the Purosangue, the 4RM-S system developed for the GTC4Lusso has been further evolved and now
inherits the innovations made to the control logic developed for the SF90 Stradale’s 4WD system, coupled
with the new independent 4WS seen on the 812 Competizione. Yaw management in cornering when
accelerating is therefore optimised by a combination of Torque Vectoring on the front axle, distribution of
torque to the rear tyres by the E-Diff and the generation of lateral force by the 4WS. The new electronic
management delivers a significant increase in performance in relation to precision of control of the position of
each single actuator, faster axle response time and consequent improved precision of the lateral force
generated.
All the above technologies are incorporated in the 8.0 version of the Side Slip Angle Control which feeds a
shared language to all the controllers to identify the best way to maximise performance. The SSC 8.0 in fact
integrates all the car’s controls (steering, traction and vertical control) active on all four corners of the car and
creates a natural synergy with the new ABS evo.
Particular emphasis has been placed on new objective longitudinal indicators of driving thrills specific to the
Purosangue’s performance targets. Alongside traditional constantly increasing acceleration figures and
reduced response times, in-gear acceleration when in manual has been honed to emphasise the superb
elasticity and pick-up that are most definitely unique to the Purosangue.
The Purosangue exploits the new 8-speed DCT’s potential from all angles: mechanical, power and control.
The ratios are the same as on the SF90 Stradale and 296 GTB. With larger tyres, this solution gives ratios
that are shorter than on previous Ferrari 4-seaters to the benefit of more progressive performance under
acceleration. The eighth gear is designed for a more relaxed experience in long-distance driving.
The transmission’s software control benefits both in terms of performance contents (reduction in Up and Down
shift times of around 18%) and the “Sailing” function which allows the engine and gearbox to be automatically
decoupled to guarantee greater smoothness in driving situations where traction isn’t required (and thus also
under braking). The Purosangue’s Manettino strategies were also redesigned to suit the project’s
specifications.
The Purosangue offers an impressive array of driver assistance (ADAS) features as standard, many of which
were developed in collaboration with Bosch®, including Adaptive Cruise Control (ACC), Automatic Emergency
Brake System (AEB), Auto High Beam (HBA/HBAM), Lane Departure Warning (LDW), Lane Keeping Assist
(LKA), Blind Spot Detection (BSD), Rear Cross Traffic Alert (RCTA), Traffic Sign Recognition (TSR), Driver
Drowsiness and Attention (DDA), and rear-view parking camera (NSW).
A function being made available for the first time on a Ferrari is HDC (Hill Descent Control), which helps the
driver to maintain and control the car’s speed, shown on the dash, on steep descents. When HDC is
activated, it controls the braking system to guarantee that the car’s speed does not exceed that set on the
display. It can, however, be manually overridden by using the accelerator pedal.
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