Honda CR-Z, 2011

 

 

 

 

 

Honda CR-Z, 2011

The Honda CR-Z‘s exterior styling is formed around a "one-motion wedge" concept with a low bonnet line and wide stance giving the car a confident, athletic look. Signature Honda design features, such as the split level rear glass hatch and aerodynamic, shallow raked roofline have been referenced in the design of the sleek coupe and then combined with a curvaceous and deeply sculpted exterior form.

The overall power output of the engine and IMA system is 124 PS and a healthy 174 Nm of torque. The peak torque figure is identical to that of the 1.8-litre Civic and arrives at just 1500 rpm, a level where previously only turbocharged engines deliver their maximum. Even with torque levels directly comparable with a Civic, the Honda CR-Z emits 35 g/km less CO2 than its conventionally powered cousin. Other harmful exhaust emissions are also very low and the Nickel Metal Hydride battery pack can be recycled through Honda dealers, at the end of the vehicle's life.

For the first time, a fuel efficient, low emission parallel hybrid system is combined with an ultra precise 6-speed manual gearbox. The manual gearbox is a core part of the driver engagement Honda's engineers wanted to bring to the Honda CR-Z model. The flexibility of Honda's unique IMA parallel hybrid system allows it to be used with a range of transmissions, not just CVT-based gearboxes.

The manual transmission is complemented by a 1.5-litre 4-cylinder i-VTEC engine, which is new to Europe and is a key component in the Honda CR-Z's unique character. This powerful, yet efficient engine is based on the engine fitted to some non-European versions of the Jazz. The eager to rev nature of the medium capacity engine, is enhanced by the additional 78 Nm of torque provided by the 14 PS electric motor, which is situated between the engine and clutch. The electric motor boosts torque at low and medium revs, which gives the Honda CR-Z in-gear flexibility more usually associated with turbocharged engines.

To maximise driver choice and enhance the day to day driveability of the car, the Honda CR-Z is fitted with a 3-Mode Drive System. This unique feature allows the driver to choose between three driving modes, which alter the responses of the throttle, steering, climate control and the level of assistance provided by the IMA system. In developing this new facility, Honda allows the driver to adapt the car's settings to enjoy their favourite road, maximise economy, or strike a balance between the two.

Sport buttons have become commonplace, usually offering a sharper throttle response, but Honda's 3-Mode Drive System is different. The new system alters the behaviour of the hybrid drivetrain and the power steering assistance as well as the throttle mapping between the three modes.

When the Honda CR-Z driver is away from the town or city and wanting to enjoy the open road, they can put the car into SPORT mode. This sharpens the throttle response, changes the behaviour of the IMA hybrid system to provide more electric motor assistance and increases the weight of the electric power steering.

At all times the car can be run in NORMAL mode, which provides a balance between performance, economy and emissions and suits most driving situations.

The ambient lighting of the speedometer is used in the same way as in the Insight to guide the driver in driving more economically and ecologically. In addition to the Eco Assist function, the Honda CR-Z's meter lighting is linked to the 3-mode drive system. In NORMAL mode and ECON mode the speedometer is illuminated blue, glowing green when driven economically. In ECON mode it has a green eco flower lit in the mode indicator. When the speedometer is illuminated in a red ambient light, this indicates the Honda CR-Z is in SPORT mode.

The exterior design of Honda CR-Z deliberately evokes the iconic style of the 1980s CR-X, which was originally developed to provide a small, stylish car that could achieve spectacular economy. Signature features of the CR-X, like the split level rear glass hatch and low shallow raked roofline have been referenced in the design of the sleek coupe and then combined with a curvaceous and deeply sculpted exterior form.

The shallow raked roofline and sharply truncated tail of the Honda CR-Z is a feature shared with many Hondas past and present, including the CR-X, 1999 Insight and the FCX Clarity. All of these cars have been designed to cut through the air with minimal disturbance, reducing drag to lower fuel consumption and emissions. The Honda CR-Zs headlights are accented with LED day time running lights, which are positioned in the lower section of the front lights. This is the first time LED running lights have been applied to the front of any production Honda car and help to emphasise the wide sporting stance of the new hybrid coupe.

The interior of the production car has been influenced by the cabin of the 2007 Tokyo Motor Show Honda CR-Z Concept, especially the 3D speedometer and driver focussed cabin. The high-technology instrument binnacle places all of the commonly used controls close to the driver's hands, allowing full concentration on driving at all times.

Equipment levels on the Honda CR-Z are generous with all grades benefitting from six airbags, active headrests, Vehicle Stability Assist and Hill Start Assist. All CR-Zs will also come fitted with Climate Control, 6-speaker CD player, USB iPod® link and an engine start button. Middle and top grades benefit from leather seats, steering wheel audio controls and alloy pedals. Top grades gain Bluetooth® Hands Free Telephone controls, Cruise Control, Panoramic Glass Roof, HID lights and 360W high power audio system - including a boot mounted sub-woofer.

The stylish interior has a 2+2 layout, opening up the possibility of carrying smaller adults for short distances or children on longer journeys. The one-touch motion folding rear seats open up a flat floored cargo area, that gives a surprising 382 litres of cargo space, on a par with most C-segment hatchbacks, allowing a wider range of luggage to be carried. The flexible luggage area also has an under-boot area of 19 litres to stow additional cargo, or store items out of sight.

The chassis was an important factor in the development of the new car, with driver enjoyment being a core part of the design brief. The platform shares some components with the Jazz and Insight models, but the wheelbase, track width and set-up are all unique to the new hybrid. Overall the Honda CR-Z has a 115 mm shorter wheelbase and is 310 mm shorter in overall length than the Insight, enhancing agility and reducing kerb weight by 57 kg compared to its 5-door, five-seat, family car cousin.

The Honda CR-Z suspension features unique, springs and dampers setting and the tolerances are also unique. One of the major detail changes is the adoption of a forged aluminium lower arm in the MacPherson strut front suspension to replace the Insight's pressed steel items. This reduces weight of each wishbone by 2 kg and also increases strength to cope with the wider track width and tyres.

EXTERIOR DESIGN AND BODY
The Honda CR-Z was created from a project to create a sporty coupe for the second decade of the 21st century. The compact dimensions, light weight construction and aerodynamic design brings a dual benefit of improving performance, but also cutting fuel consumption and emissions.

The design has hints of Honda's past with the split level window and shallow sloping roof, combining them with complex curves and deeply scalloped panels that would have been impossible to mass produce just a few years ago.

Modern car design has many constraints placed upon it, with the increasing number of regulations and policies which influence the shape of new models. The major challenge that faced Honda's designers and engineers was to maintain the sleek low bonnet design of the initial design studies, while adopting the 1.5-litre engine with IMA system and complying with pedestrian impact requirements. Honda's engineers worked tirelessly with the designers to reduce the height of the engine, as well as working on suspension and body hard points to allow for sufficient clearance for bonnet deformation.

The wide and low stance is enhanced at the front end by the unusual one piece grille, which extends above and below the front bumper line. This grille is a key feature of the car's "face", with a pronounced raised area of the bonnet flowing from its top line right up to the base of the windscreen. The wide tapering headlights, with day time running lights elegantly integrated into the lower edges, extend towards the edges of the strongly flared wheels arches.

Aerodynamics
The door mirrors are an ultra aerodynamic, shape, supported by a wing form stay, which combine visual appeal, with low drag design. Extensive aerodynamic testing led the design team to the final shape, which integrates a slim indicator repeater to complete the look.

The roof slope and length is critical to the overall aerodynamic performance of a vehicle and the stylists and engineers worked together to create the longest roof length possible without upsetting the overall visual balance of the car.

The curvature and shape of the rear hatch and glass area are a part of the drag reduction measures that have been used throughout the Honda CR-Z's design, as well as bringing a fresh perspective to a signature Honda design feature. Great attention was paid to maximising visibility through the rear hatch and the size and position of the spoiler which divides the two areas was very carefully researched and tested.

Body Structure
To achieve the radical looks of the Honda CR-Z Concept, required innovative solutions to ensure the styling did not compromise the usability or dynamic responses of the Honda CR-Z. The engineers wanted to create a stiff body unit to ensure dynamic responses met the expectations the styling creates. To achieve this, metal gussets are used in critical areas around the front and rear suspension turrets to provide a firm base for excellent suspension control. Furthermore an H-shaped "performance rod" was designed for the rear to increase rear chassis stiffness. The result of these stiffening efforts is a rigidity figure similar to that of the European Civic Type R.

INTERIOR DESIGN
The interior styling of the Honda CR-Z Concept was warmly received and Honda's engineers and stylists were keen to reflect this in the production car.

The cabin of the Honda CR-Z has been designed around a cockpit theme, clustering critical controls close to the driver, creating a sense of purpose and reducing distractions. The upper dashboard section contains all of the controls and dials and is formed from a RIM (Reaction Injection Moulding) moulded black plastic, which has never been used for a Honda dashboard before. This new plastic material gives a pleasing, tactile to the upper dash surfaces.

Instrumentation
The rev-counter forms the centre piece of the dashboard with the speedometer recessed in to the middle of dial. The rev-counter performs a full scale deflection from zero to maximum and back again at start-up, drawing the driver's eye to the instrument binnacle when switching the car on.

Either side of the speedometer and rev counter are the ancillary gauges and displays, for less critical information. To the right of the centre, are the fuel gauge and fuel economy meters and below these is the Multi-Information Display (MID). On the left of the central gauge, are the IMA battery level gauge and the charge/assist gauge, which shows when the motor is assisting, or the battery being recharged.

The MID can display elapsed journey time, current fuel economy, average fuel economy and average speed. The MID can also display the current status of the motor and engine in providing power and the Eco Assist bar, which gives detailed guidance on driving style and avoiding excessive acceleration and braking when economy is the goal. Drivers can also check the economy figures achieved on their previous journeys as well as their progress towards the Eco Assist awards.

The instrument area is framed by two wing-like extensions to the instrument cowl which contains the controls for frequently used equipment, placing them close to the driver's hands. On the left "wing" the controls for the 3-Mode Drive System are clustered alongside the controls for the door mirrors.

Interior Flexibility
The stylish interior has a 2+2 layout which gives the possibility of extending usability beyond that of a two seat car and are also fitted with ISOFIX child seat points. The rear seats have been designed to fold easily and quickly to significantly increase cargo space. The one touch motion folding rear seats can easily be folded, even if standing behind the car, quickly extending beyond the standard 214 litres (VDA) of space. Folding the seats opens up a flat floored cargo area that gives a surprising 382 litres (VDA to window) of cargo space, allowing a wider range of luggage to be carried.

Equipment
Equipment levels on the Honda CR-Z are generous, with all grades benefitting from 6 airbags, active headrests, Vehicle Stability Assist and Hill Start Assist. When starting on steep inclines from a stop, Hill Start Assist temporarily prevents the vehicle from rolling backwards by maintaining brake pressure during the moment between releasing the brake, depressing the throttle and engaging the clutch (for a duration of approximately 1.0 second).

ENGINE AND IMA SYSTEM
The Honda CR-Z is the first car to combine a 1.5-litre i-VTEC engine and the IMA system, giving excellent fuel economy and great emphasis on driver enjoyment. This 114 PS engine is combined with a 14 PS electric motor which also boosts torque, with an impressive 78 Nm at low to medium engine speeds. The combined power figure peaks at 124 PS with a healthy 174 Nm of torque.

Performance and driver enjoyment can be seen as a conflicting need to good fuel economy and exhaust emissions levels. The CR-Z's 1.5-litre, 16-valve, i-VTEC, petrol engine provides driver enjoyment with its enthusiastic engine note, willingness to rev and broad spread of torque. At the same time its modest capacity, boosted by an electric motor can achieve excellent fuel economy and low overall exhaust emissions, including the all important CO2 emissions. The CR-Z is the first Honda hybrid, since the original 1-litre Insight to use a four valve per cylinder head with the IMA system.

The Honda CR-Z emits just 117 g/km of CO2 on the EU test cycle and consumes just 5.0 l/100km of fuel. This CO2 figure is just 1 g/km higher than the original Civic IMA, an incredible achievement considering the over 30 PS power advantage the CR-Z has over its saloon ancestor.

The Honda CR-Z engine used is based on the 1.5-litre Jazz unit with changes to the valve timing allowing for one intake valve to be deactivated at low engine speeds. This creates an additional swirl effect which enables fast combustion and higher exhaust gas recirculation. The effect of this additional turbulence is to reduce emissions and improve fuel consumption. At higher revs, both intake valves are opened to increase power output.

Numerous small changes are made to the engine to suit the characteristics of the Honda CR-Z, integration of the IMA system and installation in the coupe body. The original engine, as it was installed in the Jazz, would not fit under the low bonnet of the car as it stood. The development engineers developed a new intake manifold and a flat air cleaner assembly, to give sufficient clearance and allow space for pedestrian impact protection.

The 1.5-litre i-VTEC engine has not been seen in an EU specification car before and was chosen for its combination of light weight, fuel efficiency and compact size. The block of the 1.5-litre engine is similar to other Jazz engine variants and the Insight meaning that integration of the IMA system is simplified. Because the basic block layout is shared with the 1.3-litre Insight engine, the sump pan that was developed for that car was adopted. This measure assisted the team in the task of reducing the overall engine height and lowering the position in the chassis.

IMA System

The IMA system is shared with the Insight hybrid, but the software and settings have been altered to interact with the 3-Mode Drive System and manual transmission. Although the operating revs are quite different in a manual car, the flexibility of Honda's IMA parallel hybrid system makes integration of different engines and transmissions more straightforward.

The electric motor provides its peak torque instantly from the start, boosting the low end torque of the Honda CR-Z by more than 70 Nm, improving initial acceleration. The torque curve of the new hybrid is unusually flat for a naturally aspirated engine, with the peak arriving at just 1500 rpm, enabling great flexibility at all engine speeds.

The battery pack in the Honda CR-Z is a 100.8 volt Nickel Metal Hydride unit which provides an excellent balance between output, reliability, safety and cost. As with the rest of the system, the battery pack is shared with the incredibly reliable Insight model, which has proved itself to have the lowest warranty claim rate of any Honda car sold in Europe during 2009. At the end of the vehicle life, the battery pack can be recycled through Honda dealers.

Exhaust Design and Tuning
To ensure that drivers would be able to enjoy driving the Honda CR-Z on the open road, the development team dedicated a great deal of time and thought to the design of the exhaust. The brief was not only to create an efficient unit that allowed the optimum operation of the engine to minimise emissions and generate the target power level, but also to produce an enjoyable sound. Because of the diversity of environments, drivers and speeds that the CR-Z was designed for, engineers would not be satisfied with an exhaust that merely had less silencing capacity.

3-Mode Drive System
The Honda CR-Z has been designed to be a car that combines driver enjoyment with excellent urban driving performance and economy. The two major roles of the car can be sometimes in opposition, with characteristics like sharp throttle response and greater steering weight increasing driver satisfaction in open road driving, but possibly proving frustrating in bumper-to-bumper traffic.

Honda's engineers have developed the 3-Mode Drive System for the Honda CR-Z, which allows the driver to alter the characteristics of the car depending on their needs and the environment the car is being driven in. By significantly altering the responses of the car, the CR-Z's new system allows drivers to adapt to different road and traffic situations.
SPORT Mode
Sport buttons have become commonplace, usually offering a sharper throttle response, but Honda's 3-Mode Drive System is different. The new system alters the behaviour of the hybrid drivetrain and the power steering assistance as well as the throttle mapping between the three modes.

When the Honda CR-Z driver is away from the town or city and wanting to enjoy the open road, they can put the car into SPORT mode. This sharpens the throttle response, changes the behaviour of the IMA hybrid system to provide more electric motor assistance and increases the weight of the electric power steering.

ECON Mode
Honda recognises that even the most enthusiastic driver may regularly experience heavy traffic, where maximising fuel economy is more desirable than the perfect line through a corner. In these situations ECON mode can be selected, which prioritises fuel economy in the operation of the drive-by-wire throttle, ECU, air conditioning and the hybrid system. For those times when spirited driving is not possible or desirable, the Eco Assist function, in conjunction with the ECON mode, allows the driver to enjoy beating their best economy score on the way to work, or in heavy traffic.