| | |||||||||||||||||||||||||||||||||||
Lexus unveiled the IS-F high-performance luxury sedan today at the 2007 North American International Auto Show (NAIAS) in Detroit.
The all-new 2008 IS-F high-performance luxury sedan will deliver more than 400 horsepower from a 5.0-liter V8 engine when it goes into production. The exciting new car make a dramatic statement of Lexus performance. Prominent in the vehicle, the "F" designation was first conceived nearly 20 years ago with a project internally coded "Circle-F," with the "F" standing for "flagship." This was the original code for what became the Lexus Division. The Circle-F designation further evolved into the code name Flagship One, or F1, and the first F1 concept developed into Lexus’ first vehicle, the LS. Since then, the "F" code has come to signify a special vehicle program within Lexus that falls outside the normal engineering and development process. "Lexus has long been perceived as the maker of mainstream luxury vehicles, the unveiling of the IS-F only changes this perception, it also introduces a new Lexus marque," said Bob Carter, Lexus Division group vice president and general manager. "The ’F’ shared by both vehicles is the signature for a new high-performance marque conceived by an engineering team that dared to turn their dream of ’a Lexus like no other’ into a reality." The "F" originates from the "Circle-F" internal code for what became the Lexus Division nearly 20 years ago. Since then, the "F" code has signified special Lexus vehicle programs that fall outside the normal engineering and development process. The Look of PerformanceBased on the IS luxury sport sedan, the IS F is clearly differentiated when viewed from the front, rear or in profile. A trapezoid-shaped front bumper fascia, a theme that is repeated at the rear, sets off the V-shape grille. The hood has a raised center section to make room for the V8 powerplant, and the front fenders were widened to envelop the 19-inch low-profile tires. Both upper and lower grilles use a special wire-mesh pattern, and total grille area is increased to ensure adequate cooling for the 5.0-liter V8. The lower grille is flanked by large brake cooling ducts adjacent to standard fog lamps. Standard bi-xenon HID headlights include the Lexus Adaptive Front lighting System (AFS), which helps to illuminate curves at night. Contributing to both design and performance, 19-inch forged-alloy wheels produced by BBS® feature a distinct dark-gray finish and an asymmetrical 10-spoke design. ---- IS-F Performance SedanMuch of the development of the new IS-F took place at Fuji Speedway and the Higashi-Fuji Technical Center in Japan. The IS-F is based on the proven rear-wheel-drive Lexus IS, which is equipped with a double-wishbone front and multi-link rear suspension. As well as the IS performs, Lexus engineers demanded much more of the all-new IS-F. The result is a performance tuned 5.0-liter V8 engine, topped with specially engineered heads fed by a two-stage intake system, that produces 400-plus horsepower and more than 350 ft.-lbs. of torque. The all-new IS-F is equipped with engine-oil and transmission-fluid coolers for high-speed performance and a cylinder head-scavenging oil pump for high g-force driving. The IS-F engine is mated to the world’s first eight-speed direct sport-shift transmission. A new torque-converter lock-up control was developed that allows for a direct, crisp gear change through the constant lock-up of the torque converter in second through eighth gears. In Drive mode, the IS-F transmission performs with great smoothness, and the torque converter allows for great launch ability for fast standing-start acceleration that will register a zero-to-60 time in less than 4.9 seconds. The IS-F features custom-designed 19-inch forged alloy wheels as standard. The wheels were built to Lexus specifications by BBS and are surrounded by high-performance sport tires. The attention to performance is complemented by modified styling cues that differentiate the IS-F from the standard IS. Lexus engineers provided the IS-F with a dual-exhaust system and quad-tail pipes, wider front fenders, and a larger grille and rear spoiler. Both the hood and lower intake were enlarged to accommodate and cool the V8 engine. ---- IS F Engine, from the Bottom UpThe 2008 Lexus IS F is exclusively powered by a performance-tuned 5.0-liter V8 engine producing 416 horsepower at 6,600 rpm and 371 lb.-ft. of peak torque at 5,200 rpm. Although based on the 4.6-liter V8 used in the Lexus LS and GS, the V8 in the IS F was specially engineered for higher power output, high-performance driving and durability. This new engine’s high specific output (83.2 hp/liter) and high operating range (6,800 RPM redline) reflect the thorough attention to detail underlying the core engineering. The IS F 5.0-liter V8 is based on a die cast aluminum cylinder block with steel liners. Ribs positioned on the block’s outer wall provide high rigidity. The crankshaft is forged, with high-frequency hardening to the fillet area, and uses a double torsional damper. Crankshaft journals are polished to a mirror finish to minimize the friction generated between the connecting rods and the crankshaft, and forged sintered iron alloy connecting rods ensure high-rpm durability. Innovative BreathingHigh-flow cylinder heads designed by Yamaha have a lightweight valvetrain, contributing to the IS F V8’s high-rpm capability. The horsepower peak arrives at 6,600 rpm (just 200 rpm before redline), and the torque peak at 5,200 rpm. The resulting performance character, while quite responsive in low-speed situations, provides a rush of power at higher engine speeds. Carefully chosen ratios for the 8-Speed Sport Direct Shift transmission help ensure responsiveness at all vehicle speeds. The IS F V8 engine employs innovative new technologies to maximize efficiency and reduce emissions, including the SFI D-4 (direct-to-cylinder injection system with secondary port injectors) fuel injection and the Electronic Throttle Control System with intelligence (ETCS-i). Essentially, SFI D-4 integrates two types of fuel injection: A direct-type high-pressure fuel injection system, which provides a cooling effect in the cylinders and enables the high compression ratio (11.8:1) employed to extract maximum energy from the fuel; and a set of low-pressure port fuel injectors that help produce a precise burn to optimize power and efficiency under light- and medium-load conditions. High-Precision, High-RPM Valve ControlWith a strong bottom end to help ensure durability, the top end of the IS F V8 could be engineered for high-rpm capability. The aluminum cylinder heads made for the IS F by Yamaha feature integrated cam journals. The four composite camshafts use net-sinter forged cam lobes on hollow shafts, with the inside of the shafts serving as oil passages. Titanium intake valves operated by roller rocker arms with needle bearings and fixed fulcrums contribute to a low-inertia valve train. High-flow intake ports were specially designed for the IS F engine, with a cross-section area optimized to improve intake-pulsation efficiency and increase air-intake volume. Supporting SystemsA true high-performance engine relies on outstanding support systems and thoughtful engineering that touches every detail. The Lexus IS F’s unique stacked quad diffusers, for example, make more than a visual statement. They play an important role in a high-performance exhaust system by reducing backpressure. The stainless steel exhaust system starts with tubular exhaust manifolds and integrated catalysts. Next come dual 2.4-inch diameter front pipes that are joined before a pre-muffler and 2.7-inch single center pipe, after which the system splits into two 2.1-inch pipes and enters dual 16.8-liter mufflers. ---- TransmissionThe IS F 5.0-liter V8 engine is mated to the world’s first eight-Speed Sport Direct-Shift automatic transmission. This new transmission blends the performance characteristics of an automated manual-type transmission with the smoothness and refinement of a planetary-type automatic transmission. As a result, the driver can choose between ultra-quick manual shifts for performance driving, and smooth automatic shifts when convenience is the top priority. The driver can shift manually using either the console shift or steering-wheel-mounted paddle shifters. Driving enthusiasts will appreciate the transmission’s Manual mode (M), which will hold each gear to the 6,800-RPM redline. A pair of unique paddles located within a fingertip’s reach behind the steering wheel enables the driver to make ultra-fast up-shift gear changes. Paddle-shifting operation is allowed in either D or M modes, but shifts are quicker and more direct in M mode. At higher engine speeds, downshifts are accompanied by automated and precise throttle blips to match engine rpm to vehicle speed. Versatile Drive ModeWhen the driver selects Drive mode (D) using the console shifter, the eight-speed transmission provides quick shifts that are smooth and befitting a Lexus. At the same time, D mode offers plenty of versatility with full torque-converter lockup in 6th through 8th gears to optimize fuel efficiency. A flex-lockup clutch operates in 4th and 5th gears, continuously controlling lockup-clutch slippage to enhance fuel efficiency. From D mode, the driver can select M mode by moving the console shifter into the M slot, or can gain temporary sequential operation by keeping the console shifter in D and operating the steering wheel paddle shifters. The latter is useful for situations where engine braking is desired, such as driving through a hilly area. Sporty Manual ModeManual mode (M) goes beyond simply allowing manual gear selection by changing the transmission’s operational behavior to facilitate performance driving. In M mode, the driver will experience the feel of a manual transmission. Specifically, one will feel immediate g-force during acceleration and deceleration. In addition, the transmission uses downshift blipping control to match engine speed for high-rpm downshifts. The driver selects M mode using the console shifter, which then allows upshifts by pushing forward (+) and downshifts by pulling rearward (-). With the console shifter in M, the driver can also use the paddle shifters mounted behind the steering wheel. Shifts in 0.1 Second and Downshift Throttle BlippingNew hydraulic-control technology allows the IS F 8-Speed Sport Direct Shift transmission to perform on par with manual transmissions without sacrificing the smoothness of a torque-converter automatic. In M mode, upshifts are executed in just one-tenth of a second, six times faster than manual shifts in the V6-powered IS models. When a downshift instruction is received, the transmission control system quickly opens the electronic throttle, instantaneously increasing engine speed (blipping) to match the engine speed after the gear change. Simultaneously, the system completes the gear change by smoothly and quickly engaging the shift clutch. The downshift, with throttle blipping, occurs in just 0.2-second. ---- Sports Car DynamicsThe 2008 IS F is based on the robust IS platform, which was engineered from the start to allow a high dynamic envelope. The stiff body structure and the rear subframe are connected through several reinforcements. Spring and damper rates are increased, and larger-diameter stabilizer bars are used. The rear-suspension control arms are specific to the IS F to optimize geometry for the 19-inch wheels. In addition, the monotube shock absorbers use a larger-diameter piston rod. As on other IS models, the sophisticated shock-absorber design utilizes multi-leaf linear control valves to help improve damping force, and rebound springs offer improved body control without degrading ride comfort. The front wheels measure 19 x 8J, with 225/40R19 tires and 19 x 9J in the rear, with 255/35R19 tires. Michelin Pilot Sport PS2 and Bridgestone Potenza models were each developed specifically for the 170-mph capabilities of the Lexus IS F. Design parameters called for handling grip befitting a premium sports car but with the control and ride quality expected for a Lexus in this class. Performance-Tuned Stability ControlThe IS F is equipped with a specially calibrated version of Lexus’ innovative Vehicle Dynamics Integrated Management (VDIM) system to help provide superior handling dynamics and traction control. Combining input from a variety of sensors, VDIM is designed to anticipate the onset of a vehicle skid or slide and help correct the situation with a combination of braking, steering and throttle control in a way that is essentially transparent to the driver. VDIM integration provides precise management for Electric Power Steering (EPS), Vehicle Stability Control (VSC), traction control (TRAC), the Anti-lock Braking System (ABS), Brake Assist (BA), Electronic Brake force Distribution (EBD), and engine torque (via the electronically controlled throttle). VDIM also provides an electronically controlled brake-based limited-slip differential effect on the rear wheels. During cornering, VDIM suppresses any tendency for the inside wheel to spin, transmitting more power to the outside wheel to maintain traction and momentum. Overall, VDIM enhances handling performance by helping to control front and rear wheel slip. When braking on a mixed-friction surface, VDIM will direct steering assist in the direction that will help provide the greatest control. High-Performance BrakesThe IS F is equipped with heavy-duty Brembo® brakes designed to the specifications of the Lexus engineering team. The 14.2-inch ventilated, drilled front rotors are gripped by rigid, powerful six-piston aluminum calipers, while the 13.6-inch ventilated, drilled rear rotors use two-piston calipers. High-friction brake pads are fitted on both. The brake system gives the driver confidence in extreme usage. A single 10-inch brake booster with a tie-rod structure was utilized and tuned to improve feeling, effectiveness and firmness. Front bumper ducts adjacent to the fog lamps stream cooling air to the brakes. The brakes are finished with the Lexus name displayed on the calipers, a first for a Lexus production vehicle. ---- The Security of a LexusPassive-safety technology in the IS F begins with a reinforced passenger compartment that helps protect the occupants with front-and-rear crush structures. Seatbelt pre-tensioners and force limiters are used for all seating positions. The available Pre-Collision System (PCS) can help reduce collision damage. The package includes Dynamic Radar Cruise Control, which uses millimeter-wave radar to measure and maintain a set distance from a vehicle traveling ahead. PCS relies on the radar sensor to detect obstacles in front of the car. The PCS computer, taking sensor inputs from vehicle speed, steering angle and yaw rate, is designed to determine whether a collision is unavoidable. In such a situation, PCS preemptively retracts front seat belts and pre-initializes Brake Assist so that increased braking will be applied the instant the driver depresses the pedal. Uncompromised Lexus LuxuryLike the exterior, the interior of the IS F features an exclusive design treatment highlighted by aluminized composite trim, aluminum-rimmed main gauges, unique steering-wheel treatment and other special surface treatments. The instrument panel integrates a new oil-temperature gauge, voltmeter and shift-indicator lights, and the "F" logo is discretely showcased on the steering wheel, rear-center console and outer seat cushions. For comfort, UV-reducing, heat-absorbing glass is used throughout the car. Standard amenities include 10-way power front seats; dual-zone automatic climate control, a pollen filter and smog detector; power moonroof with one-touch open/close and seven open-position settings; power tilt-and-telescoping steering wheel; three-position memory function for front seats, steering wheel and mirrors; all power windows with automatic up/down operation with jam protection; an auto-dimming rear-view mirror with HomeLink® programmable garage door opener, automated rain-sensing wipers and heated auto-dimming outside mirrors with integrated puddle lamps. High-Power, High-Performance AudioThe standard Lexus Premium Audio System features a six-disc, in-dash CD changer, and 13 speakers. Automatic Sound Levelizer (ASL) maintains consistent sound levels at varying extraneous noise levels. A convenient mini-jack in the center console enables connection of an iPod® or other portable music players. ---- SpecificationsPowertrain
Brakes
Wheels
Performance
Dimensions (inches)
3 comments: Lexus IS-F
|
| ||||||||||||||||||||||||||||||||||
|
|
Posted on
05.3.2009 @ 00:46