Lexus is showing the IS retractable hard-top convertible at the 2009 Chicago Auto Show, Feb. 11-21. First revealed at the 2008 Paris Motor Show in October, and continuing the performance and styling trends set by the IS luxury sport sedans, the IS250C and IS350C will come to the U.S. in the late spring of 2009.
Featuring a three-panel roof that opens in just 20 seconds, the new IS250C and IS350C provide the spirited sophistication of a convertible and the sporty styling of a coupe. While the hood, headlamps, door handles and mirrors are common to the exterior of the IS sedans, all other body panels have been designed to blend seamlessly with the new three-panel aluminum folding roof.
Powered by the same powertrain as the IS sedans, the IS 250C features a 2.5-liter, 204-hp V6 mated to a six-speed manual or six-speed automatic transmission; the IS350C contains a 3.5-liter, 306-hp V6 with a six-speed automatic. Revisions to the body structure and suspension provide torsional stiffness and ride comfort with the top down, and low Lexus-like Noise, Vibration and Harshness (NVH) on par with the IS sedan when in coupe configuration.
The three-panel roof structure is completely constructed of lightweight aluminum that helps achieve smooth, quiet retraction. Unlike many retractable-roof mechanisms that increase in speed due to the weight of the structure, a unique roof-brake mechanism slows the closing roof-panels as they approach the windscreen area, ensuring easy retraction just before closure. In addition, the top completely retracts with no elements remaining in view. The three-panel folding aluminum roof also helps provide compact packaging and convenient luggage space.
The IS250C and IS350C’s new exterior design provides dynamic, unique styling when interchanging between convertible and coupe configurations. A sleek aerodynamic design and a collection of underbody covers help achieve its lowest possible drag coefficient – 0.29 Cd versus the IS sedan’s 0.27 Cd – while creating minimal wind turbulence on the cabin. An acoustic glass windshield, along with optimized seals on the roof, door and window panels, contributes to lower wind-noise levels.
A new fog-lamp design is integrated in the revised front air dam. The rear overhang increases by two inches to improve luggage space, providing storage for two golf bags in coupe configuration and one in a convertible. New combination tail-lamp clusters feature LED lights; a LED brake light is integrated within the standard rear spoiler.
The interior maintains the innovation and luxury touch points associated with the IS sport sedans, while new comfort and entertainment features provide a consistent atmosphere regardless of top configuration. Instrument gauges have been revised to help increase visibility during top-down driving, and the climate-control system has a speed-sensitive control feature that automatically increases air flow when the top is down while also automatically adjusting to vehicle speed.
The sound system has an equalizer-tuning feature that provides consistent audio whether the top is up or down, and it also automatically adapts to the natural loss of bass when the top is down.
With a four-seat configuration, the IS250C and IS350C’s rear seats feature a center console with built-in cup holders. In addition to front doors that are 11.8 inches longer than the IS sedans, a new one-touch automatic mechanism provides easier egress and ingress through quick-acting, front-seat fold-and-slide activation. Rear-seat comfort is enhanced by shifting seat position inboard, providing improved headroom. The front seat backs are configured to also provide better rear-seat legroom.
All body and chassis revisions have gone through extensive testing to ensure that the IS250C and IS350C have nearly identical NVH characteristics as the IS sedans, while still providing a consistent blend of driving performance and comfort in convertible or coupe configuration. They share common double-wishbone front and multi-link rear suspension systems with the IS sport sedan models.
A number of body-structure changes have been integrated in the IS250C and IS350C to augment strength, roll-over protection and torsional rigidity. Active safety features from the IS sedans transfer as well, including Vehicle Dynamics Integrated Management (VDIM), Vehicle Stability Control (VSC), and an available Pre-Collision System (PCS). The Safety Restraint System (SRS) will include the twin-chamber passenger airbag, while a new enlarged seat-mounted side airbag helps provide additional protection in certain side-impact scenarios. The convertible body shell has additional energy absorbing side-impact materials that also help protect front and rear passengers.