- Turbocharged motivation for Lexus IS
- Added features include rear side airbags and electrically-adjustable steering column
Lexus has combined its newly launched turbocharged engine with a traditional sports sedan configuration to provide a blend of performance, dynamics and economy to create the IS 200t. Available exclusively on the E and EX grades, the new IS 200t is the perfect accompaniment to the top-end IS 350 F Sport, which is still propelled by the sonorous 233 kW V6.
Following its unveiling in the NX 200t compact SUV, Lexus has turned its high-technology 2.0-litre four cylinder engine 90 degrees for its debut in IS’s north-south, rear-wheel drive layout. The smaller displacement turbocharged engine provides improved fuel efficiency and lower emissions whilst still delivering a stout 350Nm.
Changes to the exhaust layout and engine management system bring power levels five kilowatts above the NX 200t – to 180kW.
The 2.0-litre turbo engines strength lies in its broad spread of torque, with the aforementioned 350Nm being available from as low as 1650 rpm all the way up to 4400 rpm. This flexibility makes for effortless cruising and acceleration.
IS 200t also combines an eight-speed Sports Direct Shift automatic transmission (featuring paddle shift) with the 2.0-litre turbo engine, providing levels of driveability expected of a Lexus compact sports sedan.
The 8-speed SDS transmission has proven itself in the IS 350 F Sport and RC 350, and the latest iteration in the IS 200t has added electronic-control technology, including a Lexus-first; Downshift Lock-up Control.
The transmission also features auto-blip downshifts for added driver involvement. This all culminates in a driving experience that delivers a great balance between linear acceleration, optimum fuel economy and driveability under all conditions.
In keeping with the refined character of the IS, the transmission swaps cogs smoothly and efficiently – with the driver being able to monitor gear selection via a unique bar graph in the multi-information display.
The eight internal ratios have been chosen to balance the needs of sports driving and fuel economy, with a low first gear ratio for initial acceleration, closely spaced ratios in the intermediate gears for performance and urban-driving economy, and a tall eighth-gear ratio for freeway economy.
The now familiar Drive Mode Select rotary switch allows the driver to choose between Eco, Normal and Sport modes depending on their preference or the road ahead.
Selecting Sport mode tailors the throttle response and power steering assistance to provide a more dynamic drive. Eco mode optimises fuel economy by reducing throttle sensitivity, tweaking transmission control logic and optimising climate control operation. A dedicated Eco display mode can also be called up to relay the state of eco operation to the driver.
The ‘200t’ retains Lexus IS’s elegantly executed interior and sharp exterior styling while gaining additional features.
The 200t E and EX grade are distinguished by multi-spoke 17-inch wheels. In terms of interior accoutrements, both models are extremely well endowed. Even the E grade gets niceties such as seat heating and ventilation, 7-inch central colour display, full leather trim, electric front seats, front and rear PDC (a new addition) to name just a few of the standard items on offer. The EX grade chips in with SatNav, electrochromatic mirror and reverse camera.
The already comprehensive safety specification is bolstered by the addition of rear side airbags, taking the tally up to 10 across the range. An electrically-adjustable steering column for both rake and reach, which retracts automatically when the vehicle is turned off, further accentuates the sense of convenience and luxury on E and EX models.
On the handling front, the IS’ proven dynamics are further enhanced by the fitment of a performance damper developed by Yamaha, to counteract body roll and increase torsional rigidity.
The result is a supremely comfortably and balanced vehicle, which simply soaks up road imperfections, whilst still rewarding the driver with great dynamics and taut handling. Overall the IS 200t projects a feeling of solidity and confidence befitting that of a luxury sports sedan.
Customers have the choice of six stylish exterior colours, including a new vivid shade of red (Madder Red) and highly pearlescent Sonic Quartz white. The exterior hue of choice can be combined with either rich Ivory or classic Black leather interior. Piano Black and Titanium accents lend an air of sophistication to the cabin.
Lexus South Africa’s Glenn Crompton (Vice President of Marketing) said the new engine brings “more of the performance that customers are coming to expect from Lexus, along with quality and luxury.”
“The 2.0-litre engine gained a lot of praise from customers and critics when fitted to the NX 200t, and its addition to the IS Line has made it an even stronger proposition for customers who want a blend of performance, economy and driveability.
“The Lexus turbo engine is a high-technology affair which sits well alongside 3.5-litre V6 quad-cam powerplant.
“It’s a sensational fit for a vehicle already known for its high levels of standard specification and outstanding drive experience,” Crompton said.
New IS Turbo Engine In Detail
The new IS 200t is the first Lexus sedan to adopt the innovative turbocharged 2.0-litre petrol 8AR-FTS engine. It’s crammed with cutting-edge technology and can operate on both the fuel-saving Atkinson cycle and the conventional Otto cycle. The late intake-valve closing of the Atkinson cycle reduces pumping losses and boosts fuel economy.
Special attention was paid during the engine’s development to minimise turbo ‘lag’. This includes the use of a twin-scroll turbocharger and mounting the intercooler to the engine to minimise the intake volume downstream of the turbocharger to optimise response.
Key features of this powerplant include the world’s first cylinder head with integrated four-into-two exhaust manifold and twin-scroll turbocharger, and the latest iteration of the Lexus intelligent variable valve timing system, known as VVT-iW (‘W’ for wide).
The wider range of inlet timing variation in the VVT-iW system means the new IS 200t engine can switch instantly from the Otto cycle to the high-expansion ratio, high-efficiency Atkinson cycle according to vehicle operating conditions. Lexus has previously used the Atkinson combustion cycle exclusively in hybrid-model petrol engines.
The new 8AR-FTS engine also has the latest Lexus fuel injection system, known as ESTEC D-4ST (Economy with Superior Thermal Efficient Combustion) and an air-to-liquid intercooler. The D-4ST system splits injection between high-pressure direct and low-pressure port injection according to driving conditions, providing optimum combustion at all times.
The new turbocharged engine delivers 180kW of power at 5800rpm and 350Nm of torque from 1650 to 4400rpm endowing the IS 200t with a 7-second sprint time in the obligatory 0-100km/h dash.
It has a combined-cycle fuel economy of 7.5 litres/100km and CO2 emissions of 175g/km.
The Lexus 8AR-FTS engine is cast with low nickel content, heat-resistant steel. Cooling oil jets under the pistons improve durability and enhance warm-up performance. Twin balance shafts with resin gears minimise engine vibration to improve cabin comfort – a marked improvement in four-cylinder engine technology.
Further measures to reduce noise, vibration and harshness include an electric air bypass valve and a resonator in the intake system, to reduce the characteristic turbo noise when the throttle is closed (referred to as the ‘turbo sigh’).
The Lexus turbo-petrol engine was bench-tested for more than 10,000 hours before extensive on-road testing began, covering more than one million kilometres.
The Lexus turbo spins to 180,000rpm.
Lexus developed a new 0-20W viscosity lubricating oil without calcium content to remove the chance of engine knock at low engine revolutions.