More power and lower CO2 emissions for Discovery 4
The 2012 Discovery 4 gains a host of new and refined features making the best all-purpose vehicle even better. At the top of the list is the new ZF 8HP70, 8-speed automatic transmission, improving efficiency and helping reduce CO2 emissions on the 3.0 SDV6 diesel from a competitive 244g/km to an outstanding 230g/km.
In conjunction with the new transmission, the Discovery 4 is now equipped with the 'Drive Select' rotary gear shift and steering wheel-mounted paddle shift. Despite the reduction in CO2 emissions, Land Rover engineers have managed to increase the power from 245hp to 256hp for phenomenal performance. The 3.0 SDV6 comes equipped with a diesel particulate filter (DPF), making it among the cleanest diesel engines on the market.
In addition to the driveline improvements, the Discovery 4’s design and equipment levels have been given a makeover too. There are two new alloy wheel designs, three new option packs and improved audio and navigation systems based on the latest electrical architecture. The entry-level audio system has now been upgraded with a colour screen replacing the previous black and white unit and available with Bluetooth, DAB and USB/iPod connectivity. Also for the first time, the audio system is available with a non-navigation touch-screen. The new enhancements to the Premium Harmon Kardon LOGIC 7 system with an astonishing 825W of power through a 17-speaker system whilst the new ‘Say What You See’ voice command on premium systems allows the driver to use spoken shortcut commands.
"Improved performance, lower CO2 emissions and enhanced design and equipment levels, consolidate the Discovery 4's position as the most capable and versatile all-purpose vehicle on and off the road today. The Discovery 4 is quite simply in a class of its own," said Colin Green, Land Rover UK Managing Director.
Super-efficient 3.0-litre diesels combine more power with greater efficiency
The SDV6 engine is equipped with the ground breaking parallel sequential turbocharging system and third generation common rail fuel injection system. Throttle response is staggering with maximum torque available from only 2,000rpm.
The new 3.0-litre diesel can significantly outperform its rivals by delivering 500Nm in only 500 milliseconds from idle. This means drivers have instantaneous access to 95 percent of maximum torque. When it was introduced at 2010 model year, the parallel sequential turbocharging system was the first of its kind to be fitted to a V-engine anywhere in the world. The twin turbochargers work sequentially to provide best in class torque at low speeds and pack a huge punch at high speeds.
Driving a turbocharger requires pressure from the exhaust, creating pumping losses in the engine and increasing fuel consumption. To minimise this effect, valves isolate the secondary turbocharger both from the exhaust stream and the engine inlet tract when it is not required. A balance pipe connecting the two manifolds allows the gas from both manifolds to feed through the primary turbocharger. A variable geometry, medium-sized turbocharger is in use most of the time during average acceleration and up to motorway cruising speeds and performs with no discernible lag. It is a more efficient system than series turbocharging in which the smaller primary turbo increases pumping losses.
The 3.0-litre diesel set new standards of refinement and fuel economy at 2010 model year, with its third generation common rail fuel injection system. Operating at 2,000bar, the piezo injectors are designed to minimise noise while optimising combustion. The system operates in ‘metering mode’ supplying just the right amount of fuel to the injectors rather than returning it to the tank and wasting pumping energy in the process. All diesel models are now fitted with a DPF and have an advanced EGR system to reduce NOx.
Emissions-busting ZF 8HP70 automatic gearbox
First fitted to the Range Rover TDV8 for 2011, the remarkable ZF 8-speed 8HP70 transmission delivers unrivalled response for driving pleasure while driving fuel consumption and CO2 emissions down to an all-time low. Eight speeds provide closer ratios and a greater overall ratio spread, while the higher overdrive ratio compliments the huge torque of the 3.0 LR-SDV6, reducing fuel consumption and CO2 emissions. Efficiency is further improved by the internal mechanical layout of the 8HP70 which means that no more than two internal clutches are open at any one time.
The 8HP70 is packed with energy saving features. The hydraulic actuating system is more efficient too, the hydraulic pump drawing less energy from the engine. The torque converter is calibrated to lock-up at lower speeds and operating temperature, reducing fuel consumption and once again taking advantage of the 3.0-litre diesel engine's immense low-end torque. Transmission Idle Control seamlessly and transparently selects neutral when the car is stationary and the engine idling in drive, reducing drag on the engine and saving fuel. The 8HP70 has brains too. In hot conditions it selects a lower gear to run the engine and air conditioning pump faster to cool down the cabin quickly. In cold conditions it runs the engine faster to reduce warm-up time and emissions.
Apart from CO2-busting efficiency improvements, the 8HP70 offers performance benefits too. Taking just 200 milliseconds to complete the entire shift event, the 8HP70 gears change with an imperceptible interruption of torque for smoothness equalling that of a dual-clutch transmission, while providing a more sophisticated driving experience. The 8HP70 matches the engine speed to its turbine speed in anticipation of oncoming downshifts for an absolutely smooth transition from one ratio to the next. Closer ratios also contribute to making individual shifts smoother.
Driver Type Detection monitors driver inputs and the car’s systems to optimise the response of the gearbox to the driver’s style, while Curve Detection makes sure the gearbox avoids unwanted upshifts and holds on to the same gear when taking a sequence of bends. The gearbox also monitors the driver’s use of the brake together with the rate of deceleration to set up the correct gear for entry and exit to the corner. The 8HP70 does not have to change to a lower gear sequentially and can skip up to six ratios if necessary, for much faster response when preparing to overtake.
Driver controls include steering wheel paddles as standard enabling the driver to take control of gear shifting manually. The CommandShift lever is replaced by a rotary knob for selecting park, reverse, neutral, drive or sport modes, the last of these optimising the gearbox response times for maximum acceleration, improved response and sharper upshifts. The selector knob is flush with the centre console when the ignition is switched off, rising up when it is switched on. To avoid confusion, the Terrain Response Rotary Switch is replaced by a new Terrain Response Optimisation Switch.
"The new 8-speed transmission is a perfect match for our 3.0-litre diesel engine. The additional ratios combined with skip shifts mean the engine is always working in the most efficient part of its operating range," said Paul Walker, Chief Programme Engineer.
Advanced chassis, suspension and brakes
The Discovery 4 suspension system was substantially revised for 2010 model year with changes to roll centres, anti roll bars, suspension knuckles, damper bushes and the addition of a variable ratio steering rack for greater stability during high speed cruising and increased sensitivity at acute steering angles. More powerful brakes comprised twin-piston sliding callipers with 360mm ventilated discs at the front and single piston with 350mm ventilated discs at the rear. The understeer control system, which intervenes by automatically slowing the vehicle to bring it back under driver control, was also revised.
Off-road ability remains top of the class for 2012
When it comes to off-road ability, Land Rover vehicles are acknowledged as setting the standards for others to follow with its acclaimed Terrain ResponseTM system. For 2011, two additional functions were added, Hill Start Assist and Gradient Acceleration Control.
Hill Start Assist retains the initial driver-generated brake pressure long enough for the foot to move from brake pedal to throttle without the car rolling backwards. The brake is released after a sufficient time has elapsed or when the engine is supplying enough torque to move the car up the hill. Hill Start Assist is always available, not selectable, and neither is its operation indicated to the driver.
Gradient Acceleration Control is designed to provide safety cover on severe gradients when the driver does not have Hill Descent Control engaged. By pressurising the brake system, Gradient Acceleration Control slows the car to a limit determined by the throttle position when the car is descending the slope in the driver’s intended direction of travel. This includes descending the slope forwards in drive, or rearwards in reverse. Otherwise (such as descending while facing up the gradient with Drive selected) Gradient Acceleration Control restricts speed to 5km/h (3.1mph) for up to 20 seconds, allowing the driver to regain proper control.
"These advanced all-terrain functions have proven themselves to be world class since their introduction last year. Both are subtle but effective additions which deliver an added layer of safety to drives who want to venture further afield," said Nick Veale, Vehicle Engineering Manager.
Vision Assist Pack
A new option pack is available to customers for 2012 - the Vision Assist Pack.
Available from £1000, the Vision Assist Pack has Xenon Adaptive Front Headlamps including Cornering Lamps, Automatic Headlamps with High Beam Assist and the Surround Camera System including Approach Lamps, Tow Assist and Tow Hitch Assist.
Detail and design improvements for 2012
For 2012, crisp new steering column stalks with chrome bezels provide clearer symbols and a new premium pebble-like design to the smart key makes it both more attractive and easier to carry. Externally a new 19” alloy wheel comes as standard on the HSE whilst a Gloss Black 20” 5 split-spoke wheel design and extended Satin Black roof rails are available as customer options across the range.
The Timed Climate feature, as standard on HSE models, which pre-heats the cabin and engine in cold weather, has been upgraded from a one-day timer to a seven-day timer operated much like a home central heating programmer. Programming is accomplished via the audio system touch screen or remote control. Where touchscreen audio systems are not fitted the feature is controlled with the remote control only.
Audio, Navigation and Rear Seat Entertainment move up to another level
Discovery 4 audio systems have been rationalised and improved for 2012 and the electrical architecture upgraded to the latest MOST Gen 2.1. A new, entry level 8-speaker system with colour display replaces the previous system with black and white display. The entry level system also has options for Bluetooth, DAB and USB/iPod connectivity. The Hi-ICE
Harman Kardon System has been upgraded from 9-speakers to 11-speakers and the output boosted from 240W to a substantial 380W.
The optional Premium Harman Kardon LOGIC 7 system has seen the most dramatic improvement, from 14 to 17 speakers and an almost unbelievable increase in output power from 480W to a staggering 825W.
The higher end touch-screen audio systems were previously available only in conjunction with a navigation system but are now available independently. Navigation is available in two levels - Base and Premium, with the latter enhanced with voice activation. Touch screens have been revised with a new, contemporary style and a ‘Virtual CD Autochanger’ on models equipped with hard-disc navigation allows storage of up to 10 albums in uncompressed format on the same hard drive. ‘Say What You See’ voice activation gets over the problem of memorising commands and prompts the driver by displaying commands in a step-by-step format on the screen. Voice commands can be run together as shortcuts and the system is activated by the Push-to-Talk (PTT) button on the steering wheel.
Rear Seat Entertainment (RSE) is now equipped with a single slot DVD drive in the audio head unit so the disc can be conveniently loaded from inside the cabin. This new system replaces the previous six DVD Changer accessed through the luggage compartment. The rear seat audio system is operated by new powerful wireless technology called WhiteFireTM via cordless headphones, and can also be controlled by remote control. The system supports connectivity with games consoles and video playback of MP4 files stored on USB.
The phonebook capacity for the Discovery 4 has increased significantly for 2012 from 700 entries to several thousand, whilst the TFT Message Centre interface has been redesigned to display audio, phone and navigational information.
Land Rover Homelink takes the hassle out of homecoming
Discovery gets a brand new feature for 2011 making returning home just that little bit easier for owners with remote opening gates or garage doors. The Homelink option is packaged with High Beam Assist and can learn the frequencies of most transmitters used to operate automated garage doors and gates. The press of a button is all it takes to operate.
e_TERRAIN TECHNOLOGIES boost economy and lower CO2 emissions
The Discovery 4 is packed with features aimed at reducing fuel consumption and reducing CO2 emissions.
The parallel sequential turbocharging system of the 3.0-litre diesel makes use of its larger, primary turbo most of the time. The smaller secondary turbo remains dormant when higher power is not required, reducing pumping losses and consequently, fuel consumption. The highly efficient, third generation common rail injection system with piezo injectors and fuel metering, also makes a substantial contribution to fuel economy.
Engines have also been optimised for low-end torque as well as economy, making it possible to activate the lock-up clutch of the ZF 8HP70 automatic transmission at lower speed. This reduces ‘slip’ in the hydraulic torque converter improving both fuel consumption and CO2 emissions. The higher torque at lower rpm also enables longer gearing for more economical cruising.
The Discovery 4 incorporates several other energy saving features too. At standstill, the idle speed of the V6 is a low 710rpm, using the minimum of fuel without compromising refinement. An Intelligent Power Management System includes Smart Regenerative Charging, so whenever possible the alternator charges the battery when it is most economical to do so, such as when the car is coasting rather than accelerating.
Aerodynamic features at the front end such as the lower chin spoiler and front wheel deflectors help to reduce drag by increasing underfloor airflow. The air conditioning pump is driven through a clutch which disengages when the air conditioning is not in use, reducing parasitic losses and delivering improvements in fuel consumption and CO2 emissions.
