BY CHRIS HARRIS | 10th Aug 2007
On sale from May 1, the ground-up redesign of the LS also represents a rethink of Lexus’ flagship positioning, with the traditional single-specification V8 model – now christened LS460 – to be joined by a long-wheelbase version.
Dubbed the LS600Lh, the latter is a petrol/electric hybrid devised to recharge the moribund image of the LS to that of a technological and environmental innovator. It arrives in October, priced from around $250,000.
For now, the focus falls on the LS460, and its keen, no-options $184,900 pricing that continues the LS tradition (since 1990) of offering specification matching the German competitions’ upper-level models but at their entry-level prices.
These days, this includes Lexus’ ‘Pre-Collision’ advanced safety system, air suspension, radar cruise control, reclinable ‘premium leather’ seating with cooling and heating for all outboard seats, top-end audio, four-zone climate-control air-conditioning, and keyless entry and start.
Lexus says that equivalently equipped and powered BMW 750i and Mercedes S500 models cost between $19,600 and $69,000 more respectively, while – for LS460 money – you can only get the 200kW/350Nm 3.5-litre V6-powered Mercedes S350 and 225kW/390Nm 4.0-litre V8 BMW 740i.
With a new 4.6-litre quad-cam V8 delivering 280kW of power at 6500rpm and 493Nm of torque at 4100rpm to the rear wheels, the LS460 also has the upper hand on engine output for the outlay.
It is married to the world’s first eight-speed automatic gearbox, a compact transmission designed to maximise fuel economy at higher speeds and launch feel at lower ones. Gearshifts are said to be virtually imperceptible, and up to 41 per cent quicker than the previous six-speed automatic set-up.
Speed is an unexpected LS460 upshot – it can sprint from 0-100km/h in 5.7 seconds, hit the standing-400m mark in 13.8 seconds and reach a speed-restricted 250km/h. Apparently, 280km/h has been recorded.
Conversely, the ADR 81/01 fuel economy average is 11.1L/100km, while its CO2 emissions result is 261g/km. It is also extremely quiet – Lexus says a stethoscope is used to test each engine so buyers can enjoy the silence.
Aiding the numbers above is a leading drag co-efficient figure of 0.26Cd, with reduced lift front and rear compared to its LS430 predecessor, narrower panel gaps, minimal protrusions and a flush underbody for quieter, smoother airflow.
The LS is the latest Lexus with the ‘L-finesse’ styling language also seen on the GS and IS, which, according to design chief Simon Humphries, needed to encompass more boldness “with a degree of good taste” as well as aerodynamic efficiency.
Air suspension also makes its debut in an Australian-bound Lexus, incorporating new shock absorbers and an improved Adaptive Variable Suspension (AVS) system that automatically adjusts suspension forces at all four wheels.
It forms part of a new platform featuring a longer wheelbase and wider tracks – with the rears being the fattest among the LS’ immediate fat-cat competition.
The Lexus’ multi-link front and five-link rear arrangement includes forged aluminium components and ‘Vehicle Posture Control’ damper force control logic that uses sensors to minimise the phase difference between bodyroll and pitch angles during cornering via the shock absorbers.
Among many other things, AVS also helps reduce bodyroll by 30 per cent compared to the previous LS, along with reducing diving under brakes, squatting under acceleration, and the transmission of noise, vibration and harshness into the passenger compartment.
A Normal, Sport and Comfort switch next to the gearlever alters the damping force for flat, firmer (by 20 per cent) or softer respective responses from the suspension.
The LS460’s steering is an electronically powered set-up that, along with the front suspension’s geometry, has been redesigned for better feel, ride and handling characteristics.
Mounted forward of the front axle centres, Lexus claims the steering has a more natural feel, is more adept on rough roads, less likely to vibrate, and is more prompt in response to input.
A variable steering gear ratio is also incorporated, which quickens the direction of change at low-speed steering inputs, and decreases it as vehicle speeds rise, for a less nervous and less fidgety steering feel. Turns vary from 2.4 to 3.5 revolutions.
The driver is ensconced in a cabin that offers independent temperature adjustment as part of the four-zone climate control operation for all outboard occupants. It uses 13 sensors for optimal conditioning, and includes a permanent pollen and dust-removal mode.
Entry is via a sub-credit card-sized ‘Smart Card’ that boasts several driver-specific seat and steering wheel positioning settings.
The aforementioned Pre-Collision safety System (PCS), cribbed from the GS and some IS models, recognises potential dangers in advance according to deceleration and sudden driver inputs by “preparing” the brakes, seatbelts and dampers.
PCS joins another Lexus safety acronym: VDiM, or Vehicle Dynamics integrated Management. The latter works with the LS460’s anti-lock brakes, brake assist function, electronic brake-force distribution, traction control and VSC stability control – as well as the AVS suspension, electric power steering and variable steering system – to simultaneously help keep the LS under control and on the right trajectory, instead of relying on individual components like the VSC to work independently.
The aim is to also reduce response times, or to keep progress as smooth as possible, since VDiM can integrate each item as needed.
Ten airbags – including new rear-seat side airbags – also offer improved impact protection, while the body’s 30 per cent increase in torsional stiffness has prompted Lexus to claim another "best in class".
Lexus says that it has redoubled its efforts as far as cabin quality and craftsmanship is concerned, with the aim being to combine highly automated assembly with a custom-made effect.
"Function with emotion" is how the LS’ chief engineer, Moritaka Yoshida, put it. He went through every process of the production process to achieve this.
Expect a long-wheelbase LS460L before too long, as well as a short-wheelbase LS600h hybrid further along the line, to bring the LS line-up to at least four.