2014 Lexus IS "So, is it fun to drive?" asked head engineer Junichi Furuyama. His smile stretched from ear to ear as he stood on the rain-soaked pavement, eager to hear my impression of his two latest creations, the IS 250 and 350. The F Sport prototypes had been shipped to L.A. just a week earlier.
2014 Lexus IS
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2014 Lexus IS
Two hours prior, Furuyama had given a quick engineering briefing. One goal superseded all others when it came to evolving the new IS: He said it had to be "fun to drive," even more so than its primary competitors, the 3 Series, C-Class, and ATS. For the rear-drive-only F Sport variants, the sportiest of them all (save for the IS F), the performance bar needed to be raised even higher. Furuyama had to ensure the entire IS range -- a lineup that includes rear- and all-wheel-drive IS 250/350 versions, as well as a not-for-USA 300h hybrid -- maintained traditional Lexus standards of quietness, comfort, and practicality. Improving athleticism meant revising body rigidity and suspension calibration. The body received additional spot welding in the A-pillars, front fenders, and floor panels. More than 82 feet of stronger adhesive around the wheelwells, door frames, and engine bay, plus more laser screw welds in the floor panels, shores up critical junctures, reduces flex, and bumps up on-road stability. The front suspension's stabilizer arms are 20 percent more rigid, and the rear suspension is now a modified multilink system modeled after that of the latest GS. Toe arms were moved rearward, and springs and shocks were separated. Increased rear grip and higher pitch between suspension towers are the result of these tweaks, Furuyama noted, also allowing for more cargo room. In the 350 F Sport, Adaptive Variable Suspension stiffens damping as the driver progresses through the five Drive Mode Select commands (Snow, Eco, Normal, Sport, Sport S+). Again, as in the GS.
There is a revised GS-based electronically boosted steering setup that allows for a lighter feel at low speeds, thanks to a stroke ratio up 3 percent. A new ball screw structure provides smoother feedback throughout the steering wheel's entire rotation, and a more rigid pinion shaft reduces on-center numbness. A floating end bushing improves responsiveness to small inputs. Like the AVS, Drive Mode Select in Sport S+ changes the feel of the Variable Gear Ratio Steering depending on speed/driving situation, and is offered only in the 350 F Sport. Last year's 2.5-liter and 3.5-liter V-6 engines and their respective 204- and 306-hp outputs remain, although the rear-drive 350 gets an IS F-derived eight-speed paddle-actuated automatic gearbox. The transmission is the first to use G-Force Artificial Intelligence technology, a system that shifts or holds gears based on g-forces. All other models carry on with a six-speed automatic. World markets can expect the 300h to employ a version of the 2013 ES 300h's 2.5-liter Atkinson cycle four-cylinder mated to an electric motor and continuously variable transmission. Its battery pack is located underneath the trunk floor -- a first for the brand.
Naturally, the design has evolved as well, and poaches cues from the LF-CC concept. All exterior emotion is derived from the massive spindle grille, says Lexus; the profile's beltline begins there and tapers at the redesigned tail. Another crease starts at the sill and leads into the wraparound taillamps. Slim xenon headlamps with Lexus "arrowhead" LED running lights incorporate new Auto High Beam functionality. Slimmer "hemming" of the inner and outer fenders allows for a flusher, more aggressive wheel fitment. Laser welding fuses roof and door surrounds for a cleaner look. F Sport editions receive a chrome-trimmed spindle grille and vented nose, as well as LFA-inspired Y-spoke 18-inch wheels.
Higher grade materials line the driver-centric, horizontally themed cabin. A 7-inch display with revised navigation functionality and Lexus-first electrostatic climate control switches adds contemporary flair. For improved control and comfort, driver and passenger hip points have been lowered, as has the steering wheel's tilt angle. The nearly 3-inches-longer wheelbase, a 0.4-inch-wider stance, and heavily sculpted front seatbacks give rear passengers' knees 3 more inches of freedom. Active safety tech such as Lane Departure Assist, Blind Spot Monitor, and Rear Cross Traffic Alert can now be had with the right boxes checked. F Sport models get highly bolstered seats and a spiffy LFA-based digital F Meter with sliding menu screens.
When it comes to handling prowess, both the F Sport-tuned IS 250 and 350 prototypes have made strides in stability and predictability. The 350's variable suspension and steering calibration in Sport S+ mode deliver immediate and fluid chassis responsiveness; however, chassis-to-steering communication lacks some clarity. The smaller, less powerful 250 possesses such communicativeness in its Sport mode, and, with less weight at its nose, feels significantly more eager to jink and jive. On city streets, the 350's adjustable dampers soak up choppiness with ease, and its eight-speed transmission smoothly rolls through gears. Back in the paddock with Furuyama, I needed no time to work up an answer to his question: "Most definitely." The third-generation IS will indeed become the sportiest, most fun IS ever. But until Furuyama and Co. button down final production-spec calibrations, the jury is still out on performance. As of right now, its competition from Germany and Michigan maintain their strong upper hands. Even so, they should take heed: The Lexus IS is evolving in all the right ways.
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