It sounds like a simple enough idea: at low speed, angle the rear wheels slightly away from the turning direction to tighten the turning circle (think casters on a shopping trolley, or those rearsteerers on fire tenders carrying superlong ladders) and, at high speeds, turn the rear wheels slightly into the corner to counteract oversteer. Getting it all perfectly in sync, of course, is the trick. Four-wheel steering isn’t exactly new – it’s new featured in everything from hot Mazdas to the Nissan supercars – but it’s never quite caught on. Improved computing power has meant that it’s easier to crunch the formidable numbers needed to make the system work smoothly.
Renault’s 4Control chassis, which makes its SA debut in the Laguna Coupé, electronically controls the vehicle’s dynamics. Into the controller are fed vehicle data (such as speed and steering wheel angle) and dynamic information (steering wheel movements, yaw). That’s used to compute the effective turning angle of the rear wheels, which are “steered” by an electric actuator on the rear axle.
In an emergency avoidance manoeuvre, or under harsh braking, the system automatically adjusts the angle of the rear wheels up to a maximum of 3,5 degrees to improve directional stability. The Electronic Stability Control (ESC) is calibrated to suit a sporty driving style, and is applied gradually in unison with the rear-wheel turning action.
The Coupé’s 3,5-litre V6 engine delivers peak outputs of 175 kW and 330 N.m, and is mated to a six-speed automatic gearbox. According to Renault performance figures, the V6 accelerates from standstill to 100 km/h in 7,4 seconds and hits a top speed of 244.
Like many others from the same stable, it’s particularly strong on safety, having scored the maximum five-star rating in the Euro NCAP crash tests. In all there are eight airbags, including two new-generation adaptive dualvolume front airbags coupled with a seat rail position on the driver’s side.
The price of R499 900 includes a five-year/150 000 km warranty and a five-year/100 000 km maintenance plan.