Renault Laguna GT: new active drive with four-wheel steering

Laguna GT introduces the new Active Drive chassis with four-wheel steering, developed jointly by Renault and Renault Sport Technologies to give the ultimate in driving pleasure, handling, dynamic response and steering precision. The GT is further enhanced by the availability of two exclusive, high-performance engines: 180hp two-litre turbo diesel and 205hp two-litre turbo petrol. Thanks to its combination of advanced driving pleasure and peace of mind with a three-year/100,000 mile warranty, Laguna GT stands out as an innovative offer in the sports saloon market.

Laguna GT, which is powered by two new engines to the range, places the accent on enjoyment and efficiency to deliver outstanding on-road performance with the four-wheel steering technology. With quality an overriding concern throughout its design and production, New Laguna ensures a reassuring ride for all occupants thanks to its class-leading active and passive safety and a raft of practical features. Meanwhile, the GT's stylish looks reinforce its top-of-the-range positioning for Laguna in terms of technology and powerplants. Available in Hatch and Sport Tourer, Laguna GT goes on sale in the UK from 9 May.

Four-wheel steering for an exceptional drive
The Active Drive chassis with four-wheel steering brings many benefits, starting with improved manoeuvrability, sharpened dynamic response, and unrivalled steering precision giving the driver truly intuitive control over the cornering line, achieving new heights in driveability and active safety. In town and on country roads, the car is easy to drive: highly manoeuvrable and precise. Laguna GT corners with very little body roll and a precise line is achieved with small steering inputs. The Active Drive chassis with four-wheel steering also excels in active safety, both under difficult braking conditions (with a good control over asymmetrical grip and with the ESP matched to a more sporting driving style), and during avoidance manoeuvres at speed ('elk' test).

Four-wheel steering systems of the 1980s were essentially mechanical, with the front and rear wheels linked and pre-determined angles aimed at making up for shortcomings in the vehicle's handling (e.g. a tendency to understeer). Such systems were gradually superseded by the advent of ESP. Meanwhile, towards the end of the 1990s, manufacturers such as Nissan were beginning to develop solutions based on electrically- and even hydraulically-operated actuators to take the dynamic performance of their vehicles forward. Electronic control of rear wheel steering has enabled handling to be fine-tuned even further, notably in the case of rear-wheel drive vehicles.

The Active Drive system builds on this approach by ensuring a more dynamic and more reactive response to make the most of the inherent qualities of Laguna GT's chassis and consequently deliver even greater driving enjoyment. In addition to the complex modelling of the vehicle's handling, real-time response to the driver's instructions (every 10 milliseconds) and its ability to adapt to different conditions, Laguna GT's Active Drive four-wheel steering system means that active safety systems are only required as a very last resort, which means drivers benefit from more efficient and even more reassuring reactions when faced with an unexpected hazard.

Impressive low-speed manoeuvrability
The Active Drive chassis with four-wheel steering makes Laguna GT exceptionally easy to handle in town and agile on winding roads. At speeds of less than 38mph, the rear wheels turn in the opposite direction to the front wheels, up to an angle of 3.5°. This brings two advantages: a smaller turning circle, for easy manoeuvring; and reduced steering wheel input required thanks to the more direct, specially calibrated steering.

With four-wheel steering on the Active Drive chassis, Laguna GT has a 10 per cent smaller turning circle than with two-wheel steering: 10.80 metres, incredibly the same as Clio, instead of 12.05m. Enhanced manoeuvrability is especially noticeable in tight parking situations.

With front and rear wheels turning in opposite directions, the car effectively pivots, which means smaller steering angles are needed for the same turning effect. Whereas it takes a 16° steering wheel angle to produce a 1° turn in the front wheels on New Laguna, it takes just 13.5° with the Active Drive chassis. And this drops to 12° when the rear wheels are turned at the maximum 3.5° angle in the opposite direction to the front wheels. Because the steering is more direct, with less need for large steering wheel angles, the impression of manoeuvrability and agility is greatly enhanced. For any given bend, the driver will need less input on the steering wheel, making for more effective avoidance.

Ultra-precise steering control
From 38mph, the emphasis is on steering precision. The rear wheels turn simultaneously in the same direction as the front wheels, to enhance stability. The Active Drive system with four-wheel steering counters the centrifugal force that tends to push the rear end outwards round bends, and thus raises the safe cornering speed. The rear axle is set on the ideal trajectory, with a rear-wheel angle of less than 2° in most situations, for stability. The Active Drive chassis with four-wheel steering enhances dynamic handling, with a reassuring response for outstanding driving pleasure.

Unparalleled active safety
The Active Drive chassis with four-wheel steering also improves safety for heightened reassurance during avoidance manoeuvres. In an emergency situation, the rear-wheel angle can rise to 3.5°. The involvement of the ESP system, specially configured for a more sporting driving style, is delayed, so that the manoeuvre can be performed both safely and more swiftly. ESP only deploys when necessary, and is applied gradually because it is synchronized with the rear-wheel turn action. Via the ESP/ABS unit, the four-wheel steering control unit also detects asymmetrical braking situations, such as on mixed surfaces, adapting the rear-wheel turn angle automatically to keep the car stable with no driver action required. This helps the driver keep control during critical situations, and ensures uninterrupted peace of mind during everyday driving conditions.

Dynamic control logic
The Active Drive chassis with four-wheel steering has been developed jointly by Renault and Renault Sport Technologies and implements electronic control of the vehicle dynamics. A sensor on the steering column sends steering wheel angle information via the CAN (controller area network) to the four-wheel steer control unit, located behind the rear axle. The four-wheel steer control unit also inputs vehicle speed from the ESP/ABS unit and tracks steering wheel angle information to detect sharp steering wheel movements symptomatic of a sporting driving style or avoidance situation. All these parameters are analysed to determine the required rear-wheel turn angle, which is implemented by means of an electric actuator on the rear axle. Dynamic vehicle behaviour is precisely modelled to set the ideal vehicle trajectory at each instant, on the basis of the driver’s input and the actual situation of the vehicle. The controller and electric actuator are supplied by Aisin, a Japanese equipment supplier reputed for its experience in four-wheel steering systems.


High-performance engines
The diesel version of Laguna GT is powered by a new 2.0 dCi engine, offering best-in-class performance, driveability and acoustics. In the GT, it provides peak power of 180hp at 3,750rpm. Peak torque of 400Nm is available from 2,000rpm, with a consistent build-up through to 5,000 rpm. A reduced-inertia variable-vane turbocharger enhances dynamic response at low revs to achieve excellent performance: 29.6 seconds for the 1,000m standing start, and 0 to 62mph in 8.5 seconds. This new unit is fitted with a particulate filter and an exhaust gas regeneration valve with enhanced cooling to maximise environmental protection: combined-cycle fuel consumption is just 43.4mpg, which translates into CO2 emissions of just 172g/km. With its ultra-fast glow plugs, the 180hp 2.0 dCi unit fires into action instantly the Start button is pressed, even in conditions of extreme cold (down to -23°C).

The petrol version of Laguna GT is powered by a turbo-charged two-litre 16-valve unit (205hp at 5,000rpm and 300Nm from 3,000rpm) derived from Renault Sport technology as featured on the Mégane Renaultsport, and specifically reworked for Laguna GT, to yield the best in performance, handling and driving pleasure. Laguna GT 205 accelerates from 0 to 62mph in 7.8 seconds and takes 28 seconds to cover 1,000 metres from standstill. Fuel consumption is 34.4mpg, with CO2 emissions of just 194g/km.

Distinctive GT styling
The car's sporting character is underpinned by lateral air-intakes in the front bumper, a larger front grille and black background to the headlamps. Laguna GT sits on specific 225/45 Bridgestone Potenza tyres with new 18-inch ‘Celsium’ alloy wheels. Braking power is provided by larger 320mm diameter discs at the front and 300mm discs at the rear.

GT attributes run through to every last detail, such as the gloss black door mirrors and smoked rear lights. Laguna GT is available in four metallic colours; Mercury, Pearl Black, Venetian Red and a new exclusive GT colour, Malta Blue.

Sports interior
Externally visible on the ‘B’ pillar, the GT logo is also embossed on the light grey alcantara centre sections of the seats. As on all New Laguna versions, the interior design exudes comfort and quality for all occupants. Sports design details abound highlighting the GT version: special three-spoke leather sports steering wheel with grey stitching, drilled aluminium pedals, GT gearshift knob, sports front seats with increased lateral support and dark charcoal Riviera leather upholstery. Close attention has been paid to materials and finish, in keeping with the car’s commitment to pure motoring pleasure.

Nothing has been left to chance on active and passive safety. New Laguna, and the GT version in particular, excels in terms of active safety performance as demonstrated by the latest EuroNCAP test results. Its principal innovation concerns improved side impact protection thanks to a twin impact sensor system and new-generation double thorax/groin airbags.

The overall equipment and performance package of the new GT version sets the car apart in the sports saloon market and ensures the ultimate in reassuring driving pleasure.