New RX 450h luxury crossover

The new RX 450h luxury crossover introduces the second generation Lexus Hybrid Drive, a full hybrid system with advanced powertrain technology that delivers an unprecedented combination of fuel economy, low emissions and performance, well beyond the scope of any of its segment rivals.

All the full hybrid system’s components have been revised to achieve dramatically improved efficiency: fuel consumption is reduced by 28 per cent, while at the same time engine power is 10 per cent greater than in the RX 400h. The improvements Lexus has made also contribute to substantially lower emissions, quieter operation and greater driver satisfaction.

Total power output is 295bhp, enabling a top speed of 124mph and nought to 62mph acceleration in 7.9 seconds. This performance comes with 44.8mpg combined cycle fuel consumption and 148g/km CO2 emissions, a combination that cannot be matched in the RX 450h’s class, not even by smaller and less powerful 2.0-litre diesel models. This has a direct impact on running costs, for example in a 14 per cent benefit-in-kind company car tax rating – a level typically associated with more modest C-segment models, 'eco' specials and other hybrid vehicles, such as the Toyota Prius.

Lexus Hybrid Drive is a combined series/parallel full hybrid system that comprises a highly efficient petrol engine and two powerful electric motors. As a full hybrid the vehicle can operate on its electric motors or petrol engine alone, or with a combination of both. Like its predecessor, the RX 400h, the new model’s second, rear-mounted electric motor provides an intelligent four-wheel drive capability.

The system combines distinct front and rear driving units, with a power control unit managing their seamless, high-speed interaction.

The front drive unit features a 3.5-litre V6 petrol engine, a powerful electric motor, generator, high performance battery, power control unit (PCU) and a power split device with a planetary gear set to combine and re-allocate power from the engine, electric motors and generator as driving conditions require.

The rear unit is mechanically independent from the front. It provides four-wheel drive by means of a second electric motor, which is activated and continuously adjusted by the Vehicle Dynamics Integrated Management (VDIM) system, working in conjunction with the PCU.

Although power from the front and rear electric motors remains the same as it was on the RX 400h, at 165bhp ( 167 DIN hp) and 67bhp (68 DIN hp) respectively, the improved cooling of the PCU has increased their continuous maximum torque band width. This gives better performance, in particular from a standing start. The front and rear motors now deliver maximum torque of 335Nm and 139Nm from zero rpm respectively, while the range of the front motor’s maximum toque is extended by 9mph and that of the rear by 22mph.

News provided by www.greencarsite.co.uk

Friday April 10