The Alfa Romeo Giulietta makes its official debut today, April 13, 2010. This is an important day for Alfa Romeo because the Giulietta is to be Alfa Romeo's volume seller, but it is also an important day for us in America because it foretells what awaits us at our local Chrysler dealer. Future Chrysler C and D segment cars will utilize the Giulietta's platform (called the C-Evo).
You can read more about this here, but briefly, Chrysler will use this dynamic platform and cloak it in all new sheet metal that will be designed in America and built in America for Americans. With a chassis developed by a company world renown for producing some of the finest driving vehicles ever made, future Chrysler products look very promising.
Below are the details of the Alfa Romeo Giulietta C-Evo platform as it relates to what we could see in future Chrysler products.
A new platform to enhance road holding and agility in total comfort and safety
The Alfa Romeo Giulietta introduces an entirely new platform - Compact - designed to satisfy the most demanding customers in terms of handling, on-board comfort and safety. Furthermore, driving satisfaction and comfort can be adapted to meet every customer's specific needs thanks to the Alfa DNA selector, a device that customizes the vehicle's behavior according to three different logics (Dynamic, Normal and All Weather).
The new Compact platform continues Fiat Group Automobiles' platform rationalization strategy - preceded by the Mini platform for A segment and the Small for segments B and L0 - and is a true point of departure from previous engineering solutions due to the new content introduced, the materials used and the levels of performance achieved.
From the earliest design stages, the aim was to create a platform that would allow future Fiat Group Automobiles C segment vehicles, starting with the new Alfa Romeo Giulietta, to be ranked best-in-class in terms of handling, steering feel, performance-to-weight ratio, ride comfort, NVH (Noise Vibration Harshness), safety (active and passive) and climatic comfort.
So, the Alfa Romeo Giulietta is a completely new car capable of expressing both great agility over the most demanding routes and providing comfort on everyday journeys. Plus, thanks to a specific suspension calibration offered by the Sport Pack, the sportiness of the new Giulietta can be further enhanced.
Innovative materials and state-of-the-art solutions
First of all, the underbody represents a generational leap in terms of the materials used. The entire structure is now significantly stronger and provides better performance without any increase in weight with respect to the previous generation. All this is thanks to the ever wider use of high and ultra-high strength materials, which now make up more than 90% of the total mass of the system: some structural parts, designed to provide high strength and the ability to absorb impact with minimal deformation, have been made from hot-pressed tempered steel.
Moreover, lightweight materials have been used for several structural elements bolted to the body structure. For instance, the front beam connecting the front struts and the third load path are made from extruded aluminum. The rear bumper beam and the third load path energy absorption elements are made from Xenoy (a thermoplastic with excellent energy absorption properties in relation to weight). The third load path energy absorption elements absorb the energy of low-speed impacts with obstacles and support the bumper in impacts with pedestrians. Employing these solutions has provided a weight reduction of 8.5 kg at the front and 4 kg at the rear with respect to conventional steel structures, without compromising safety performance.
Another new feature of the underbody is its modularity, which makes it ideal for use on a family of vehicles with different wheelbases and tracks. This modularity is provided by several central floor panels and the side members and does not affect any part of the front and rear structures.
This reduces outlay to a minimum and means that the system can be applied to other vehicle systems without modification.
Many of the systems and components that make up the "Compact" architecture have been thoroughly revised with respect to the previous generation, improving performance and reducing weight (-35% for both the framework of the rear seats as well as the magnesium alloy cross car beam).
Best in class performance for comfort, handling and safety
The Giulietta offers exceptional handling performance and comfort levels thanks above all to the new suspension system employed. The MacPherson front suspension in particular was revised to offer maximum rigidity under side loads, reducing the weight thanks to the use of aluminum (saving 4 kg with respect to conventional solutions).
The rear suspension is a sophisticated Multi link that guarantees the best trade-off between handling and ride comfort without compromising the useful volume of the boot. In this case too, special attention was paid to reducing weight and, thanks to the aluminum wishbones, this suspension allows for a weight reduction of over 10 kg with respect to conventional Multi link systems.
In addition, the new electric power steering system (dual pinion active steering) ensures an excellent steering feel and is integrated with the vehicle's active safety systems. As the name itself suggests, the solution employs two pinions fitted directly onto the rack of the steering box.
The first pinion is directly connected to the steering column and guarantees direct and precise steering, without any artificial filters between the steering box and the driver's hands, affording a genuine and natural driving feel. The second pinion, again directly fitted onto the rack, is connected to the electrical actuator which is situated in the engine compartment, thus minimizing the risk of impact with passengers in the event of an accident.
The climate control system, and in particular its operating logics, were completely revised and improved, in order to guarantee the best climatic conditions in the passenger compartment, while significantly reducing over-consumption of fuel (30% less than a conventional system). Similarly, thanks to specific technical interventions, exceptional noise and vibrational quality values have been achieved.
In terms of passive safety, the Alfa Romeo Giulietta was produced to obtain the maximum Euro NCAP rating, as demonstrated by over fifteen thousand hours of mathematical modeling, 80 crash tests, 150 tests on a HyGe slide and more than 100 tests on components and sub-systems.
In detail, the new third load path increases the energy absorption potential of the vehicle front end and reduces both inertial forces and passenger compartment intrusion, thereby ensuring optimum passenger protection at higher impact severity. Safety is guaranteed by 6 airbags (as standard on the entire range); three-point seat belts with double pretensioners and load limiters; a collapsible pedal unit and steering column; the second-generation anti-whiplash system and Isofix attachments.
Lastly, in terms of active safety, the new platform of the Alfa Romeo Giulietta was designed to integrate the vehicle's different systems and exploit them to the full, thus emphasizing the three set-up functions (Dynamic, Normal and All Weather) available through the Alfa DNA selector.
This device, fitted as standard on the entire range, is designed to modify the operating parameters of the engine, gearbox (where automatic), steering system, Q2 electronic differential and braking system, in addition to the behavioral logic of the Vehicle Dynamic Control system (VDC). The Giulietta will also be introducing Pre-Fill - a new function - activated when the DNA is set to Dynamic, which provides the driver with the quickest braking response possible.
Under certain circumstances, i.e. when the control unit detects a hazardous situation requiring rapid braking, the braking system is pressurized a few moments before the driver actually hits the brake pedal so as to guarantee the quickest possible response of the system and thus reducing the vehicle's stopping distance.
These sophisticated features which improve the dynamic control of the vehicle are supported further by Dynamic Steering Torque (DST), a function which provides feed-back torque at the steering wheel that helps the driver to perform critical maneuvers correctly, before the VDC intervenes to prevent loss of control.
Segment-leading safety and dynamic behavior
The Alfa Romeo Giulietta was designed to obtain the maximum score in passive and active safety tests. In short, total protection, which makes it one of the safest cars in the field of motoring as a whole. Moreover, the new Compact platform guarantees maximum equilibrium even during extreme maneuvers.
The Alfa Romeo Giulietta comes with, as standard on the entire range, the most sophisticated electronic devices for maximum dynamic vehicle control (from braking to traction) implemented to increase dynamic limits even further, non-intrusive to the driver, but affording all-round safety. The operation of these devices has been tested through simulations and on the track with the aim of ensuring maximum driving satisfaction. Here are details of all the devices and systems used on the new car.
Braking system
The Alfa Romeo Giulietta hydraulic, power-assisted braking system comprises two crossover, independent circuits and has proven to be particularly effective to allow quick and progressive braking, with shorter stopping distances. Clearly, the system differs according to the engine version (weight and power): cars equipped with the 120 HP 1.4 Turbopetrol engine and the 105 HP 1.6 JTDM engine are fitted, on the front wheels, with 281 mm self-ventilating front brake discs and cast iron floating brake calipers with a 57 mm diameter piston.
The Alfa Romeo Giulietta equipped with the 170 HP 1.4 Turbopetrol Multiair or the 170 HP 2.0 JTDM engine are instead fitted with 305 mm self-ventilating front brake discs and cast iron floating brake calipers with a 57 mm diameter piston.
The rear wheels on all four of the aforementioned engine versions are equipped with solid rear brake discs (264 mm in diameter) with cast iron brake calipers and a 36 mm diameter piston.
Lastly, the Giulietta version equipped with the powerful 235 HP 1750 Turbo Petrol engine is fitted with 330 mm self-ventilating front brake discs and aluminum Brembo fixed brake calipers with 40 mm diameter piston; while the rear wheels are fitted with solid brake discs (278 mm in diameter) while the brake calipers are made of cast iron with a 38 mm diameter piston.
ABS with EBD
In addition to a braking system affording excellent performance levels, the Alfa Romeo Giulietta is equipped with an ABS anti-lock braking system, one of the most sophisticated currently available. It has four active sensors and a hydraulic control unit with 12 solenoid valves. The ABS system is incorporated with EDB (Electronic Brake force Distribution).
The latter distributes the braking action over four wheels, in order to stop the wheels locking and ensuring complete vehicle control in all conditions. Moreover, the system adapts its operation to wheel grip conditions and to brake pad efficiency, while also reducing the overheating of the latter.
VDC (Vehicle Dynamic Control)
VDC is Alfa Romeo's interpretation of ESP (Electronic Stability Program), a system that intervenes in conditions approaching the limit, when vehicle stability is at risk, and assists the driver in controlling the car. A sporty device, in the spirit of all true Alfa Romeo cars, featuring excellent road holding qualities, the VDC grants the driver total freedom to master the vehicle in normal conditions and only intervenes immediately prior to the situation becoming critical. The VDC is always in operation.
When there is a brisk gear change in poor grip conditions, the MSR function intervenes (Motor Schleppmoment Regelung) restoring engine torque and preventing the wheels from locking and slipping. To achieve this result, the VDC continuously checks tire grip, in both longitudinal and lateral directions, and it restores directionality and ride stability in the event of a skid. Thanks to sensors, it detects the rotation of the car body around its vertical axis (yaw speed), the lateral acceleration of the car and the angle of the steering wheel set by the driver (which indicates the chosen direction).
The device then compares this information with the parameters processed by an ECU and it sets out - by means of a highly complex mathematical model - whether the vehicle is driving round a bend within the limits of its grip or if it is about to veer (understeer or oversteer).
To return the vehicle to the correct trajectory, it generates a yaw moment contrary to the one which caused the initial instability, braking the relevant wheels individually (internal or external) and reducing engine power (acting on the throttle). This is where the peculiarity of the device made by Alfa Romeo's engineers lies. Its effect on the brakes is modulated to be as gentle as possible (therefore without disrupting driving) and the engine power reduction is contained, to guarantee sporty performance levels and maximum driving satisfaction at all times.
ASR (Anti Slip Regulation)
The ASR (Anti Slip Regulation) system is an integral part of the VDC and it optimise's traction at any speed, with the help of the brakes and engine control. Based on the number of wheel revolutions calculated by the ABS sensors, the device calculates the degree of slip and to restore grip it enables two different control systems.
If excessive power is requested, causing the slipping of both drive wheels (such as in the event of aquaplaning or when you accelerate on an unsurfaced road or a road covered in ice or snow), engine torque is reduced, decreasing the throttle's angle of aperture and consequently its air intake.
If on the other hand only one wheel is slipping (for instance the one on the inside of the bend following acceleration or dynamic load variations), the device brakes this wheel automatically without the driver having to use the brake pedal. The resulting effect is similar to that of a self-locking differential. This enables the Alfa Romeo Giulietta to handle low grip road surfaces effortlessly.
CBC (Cornering Brake Control)
The CBC (Cornering Brake Control) system is activated when the car goes round a bend while braking. In this case, the braking pressure is discharged individually onto each wheel in order to maintain vehicle stability, minimizing any understeer or oversteer.
DST (Dynamic Steering Torque)
The VDC on the Alfa Romeo Giulietta intervenes in a discreet manner owing to its combination with the DST (Dynamic Steering Torque), the 'active electronic steering' that automatically carries out corrections and also controls oversteer over surfaces with low grip.
The DST improves both driving safety and handling performance. In fact, in all driving conditions, the electronic steering suggests the correct maneuvers for the driver to perform, allowing excellent grip performance and providing a great sense of safety. This is thanks to the continual interaction between the electric power steering (which generates the torque at the steering wheel) and the electronic dynamic driving control (VDC).
In detail, the DST automatically carries out corrections, helps maintain vehicle control and makes the intervention of the VDC more discreet.
The DST system is especially useful in the event of oversteer, aiding the most appropriate maneuver to maintain vehicle control in all conditions. Moreover, the MCF (Mu-Split control function) intervenes when driving on surfaces with different grip (for instance, it is often the case in winter when two wheels are on ice while the other two are on the tarmac).
In this case in particular, the DST system makes automatic counter-steering possible, permitting vehicle control (and avoiding the car spinning around) while at the same time minimizing the stopping distance (which is reduced by 10%). Lastly, in sporty driving conditions, if the system detects greater lateral acceleration (from 0.6 g) it intervenes, by providing increased resistance torque to the steering wheel. This way, it considerably improves the driver's sense of mastering the car on bends, especially at high speed.
HBA and Hill-holder
The Alfa Romeo Giulietta range is completed by the HBA system, the hydraulic brake assistance device that automatically increases brake circuit pressure under emergency braking situations. And the Hill-holder system which, for a hill start, maintains the braking action for a few seconds after the brake has been released, thus facilitating setting off and avoiding the car moving backwards.
Electronic Q2
The Alfa Romeo Giulietta is fitted with a new Electronic Q2 system which improves the transfer of drive torque to the wheels and, in particular, guarantees excellent cornering behavior thus making the car safer and more enjoyable during a sporty drive or in poor road grip conditions.
In detail, the Electronic Q2 system is based on exploiting the braking system which, controlled appropriately by the VDC control unit, creates a vehicle behavior very similar to a limited slip differential (so the Electronic Q2 system electronically simulates the presence of a self-locking differential).
In particular, the front braking system, in cornering acceleration conditions, acts appropriately on the inner wheel, increasing the drive of the outer wheel (with more load) and distributing the torque between the front drive wheels dynamically and continuously according to the driving conditions and the road surface.
Alfa DNA and the new Pre-Fill function
The new model is fitted with the Alfa DNA system, an innovative system which controls the main driving parameters (engine response, stability control and steering assistance).
Until recently available only for racing cars or supercars, the Alfa DNA system acts on the engine, brakes, steering, suspension and gearbox, allowing three different vehicle behavior modes, depending on the most suitable driving style for the conditions or the desires of the driver: sporty (Dynamic), urban (Normal), and maximum safety even in low grip conditions (All Weather).
The selector is located in an ergonomic position – in front of the gear lever on the tunnel – and allows the driver to select one of three operating modes, simply by moving the lever (the selection is displayed by a specific LED switching on together with a message on the instrument panel display).
In detail, for those who want relaxed, safe driving, in Normal mode each individual component affected by the Alfa DNA system are in its normal configuration: lively engine, highly discreet Vehicle Dynamic Control and a DST (Dynamic Steering Torque) which sees that oversteer is avoided.
If on the other hand the driver prefers a more sporty driving style from the new Alfa Romeo Giulietta, the lever can simply be moved to the Dynamic setting: in this mode, DNA affords a unique driving experience, thanks to the fact that the system makes the VDC and ASR less intrusive (so the vehicle dynamic control is a little more detached from the electronic control) and concurrently enables the Electronic Q2 system.
Moreover, again in Dynamic mode, the Alfa DNA also acts on the steering and engine to offer a truly complete and enjoyable sporty experience. The steering is less power assisted and gives the driver a more sporty feel, guaranteeing perfect control.
The Giulietta is also introducing Pre-Fill - a new function (activated when the DNA is set to Dynamic) which uses the VDC system to provide the driver with the quickest braking response possible. In detail, the control unit recognizes the driver's desire to brake from the speed at which accelerator pedal is released. At this point the VDC increases the pressure inside the braking system by several bars to take up any play and create the sensation of quicker braking response and reduce braking time.
The third mode enhances the traction control effect and enhances response to mu-spit (the DST function - active electronic steering) which intervenes when driving on surfaces with different grip (for instance, it is often the case in winter when two wheels are on ice while the other two are on the tarmac). When the selector is set to All Weather, the Alfa DNA system makes the car easier to control even on low grip surfaces (on wet or snowy surfaces, for instance), acting on the vehicle dynamic control, lowering the VDC intervention threshold.
Chrysler 200C: Could the C-Evo chassis show up underneath this beautiful car?
With thanks to Fiat Group Press and Chrysler Media
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