EXHILARATING PERFORMANCE

The UX has been engineered to deliver "elegant performance with peace of mind" consistent in all Lexus models. The foundation is the new global architecture platform named GA-C, used for the first time in a Lexus.

Two new powertrains make their debut: a new, fourth generation self-charging hybrid system with 178 DIN hp/131kW1 and the choice of front wheel drive or E-Four in the UX 250h; and a new 2.0-litre petrol engine with high thermal efficiency, available with a new Direct Shift continuously variable transmission in the UX 200.

Suspension, steering and tyres have also all been developed to support Lexus' dynamic and performance ambitions for the UX.

First use of new global architecture platform named GA-C

The UX is the first Lexus to be constructed using the new global architecture platform named GA-C, the foundation for the car's dynamic performance. Its development focused on giving the UX nimble and instant response to the driver's inputs, while communicating a sense of stability and safety.

The platform allowed for an increase in rigidity, including a high-tensile and ring structure around the rear and back door openings. Highly rigid adhesive and Laser Screw Welding have been used in key locations, greatly enhancing overall rigidity.

Low centre of gravity

The UX has the lowest centre of gravity of any vehicle in its class, thanks to the design of the global architecture-C platform. This characteristic, central to the car's fine ride and handling quality, is also supported by weight-saving measures in the body construction, including the use of lightweight aluminium for the side doors, fenders and hood, as well as a resin material for the back door.

Suspension and steering

MacPherson strut front suspension and a double wishbone arrangement at the rear have been designed and tuned to promote ride comfort and sharp response. Special attention has been paid to shock absorber performance and the quality of the damper oil, oil seals and friction control.

An Electric Power Steering system with a new compact and highly rigid column assist has been adopted for the UX, with a larger diameter column shaft. This supports handling with crisp, immediate response to driver inputs, with good steering feel.

Fourth generation self-charging hybrid powertrain

The Lexus UX 250h will also use a new fourth generation hybrid electric system that features a new 2.0-litre four-cylinder petrol engine and continuously variable transmission (CVT). It will be available both with front-wheel drive and with Lexus' E-Four.

The new engine is notable for its high thermal efficiency and output, with provisional performance figures for the full hybrid self-charging system (engine and electric motor combined anticipating a maximum 178 DIN hp/131kW).

The powertrain development programme focused not just on outstanding fuel economy, but also on a high level of driving appeal. Particular efforts were made to reduce any "rubber band" effect in the operation of the hybrid system and transmission, by optimising the level of electric motor assistance and engine rpm to generate a linear acceleration feel without the engine running at high revs. Engine rpm are synchronised with the increase in vehicle speed to create an immediate and continuous acceleration feel, responding to the driver's intentions and creating a pleasant driving feel.

New hybrid transaxle, power control unit and battery

The system has a compact and lightweight new transaxle and Power Control Unit, designed to minimise power losses through heat and friction.

A new nickel metal-hydride (NiMH) battery is used with a revised construction and more compact cooling system that allows for smaller dimensions overall. This allows the battery to be located below the rear seat, minimising intrusion in the load space and supporting the UX's low centre of gravity.

E-Four

The E-Four system gives the UX 250h all-wheel drive capability by placing an additional electric motor on the rear axle. Power distribution between the front and rear axles is automatically optimised when accelerating, cornering, or driving on slippery surfaces. When a loss of rear-wheel grip is detected, the amount of power that can be directed to the rear of the car has been increased from 60 to around 80 per cent, at speeds up to 70km/h, contributing to excellent handling stability.

UX 200 with new 2.0-litre petrol engine

The UX 200 is powered by a new 2.0-litre petrol engine, engineered to provide a high level of dynamic and environmental performance with excellent fuel economy. The in-line four-cylinder unit uses high-speed combustion to achieve enhanced thermal efficiency.

Features which enable this across a wide range of driving scenarios include multi-hole direct fuel injectors, a continuously variable capacity oil pump, a variable cooling system and VVT-iE intelligent variable valve-timing on the intake side. The result is a maximum thermal efficiency of around 40%―a best-in-class level for a passenger vehicle engine.

Direct Shift-CVT

The new 2.0-litre engine featured in the UX 200 is matched to Lexus' first Direct Shift-CVT, engineered to provide the smooth, fuel-efficient performance of a conventional continuously variable transmission, but with a direct driving feel.

A conventional system uses two pulleys, connected by a belt, that can change their radius seamlessly, and thus change the effective gear ratio, without any "step" effect.

The new Direct Shift-CVT has additional gears to achieve acceleration at start-up like a manual transmission. This gives the smooth acceleration of a CVT, but with a direct acceleration feel.

In addition, this use of gears for acceleration from start-up reduces the need for the CVT's pulleys and belt mechanism to be used in the low gear range. This allows more room to be dedicated to the higher gear range.

High-speed, high-response gear-shifting technology, using a multiplate wet clutch developed for use in automatic transmission, is used to switch power from the gear to the belt and pulleys. This secures performance in response to different situations, from smooth and fuel-efficient driving to sporty performance with fast shifts.

The design also maintains the benefits of a CVT, which can freely adjust the gear ratio to simulate changes like multi-gear automatic transmission under heavy acceleration. This gives linear acceleration feel with synchronisation of the increasing engine revs and vehicle speed.