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One of our cite sponsor's is posting a variety of Lexus Stories.

The Engine Story
The VDIM Story
The Transmission Story
The Brake Story
The Suspension Story

All of those are good reads, and I'll leave those for him to post. However, some of you may find the below Lexus Product Announcement interesting:

2008 Lexus IS F Sport Sedan

In addition to the exclusive V8, the 2008 IS F's performance
credentials include racetrack-developed suspension and braking, and
a specially calibrated version of the advanced Vehicle Dynamics
Integrated Management (VDIM) system. Much of the IS F
development took place at racetracks around the world including
Germany's legendary Nurburgring Nordschleife, Circuit Paul Ricard in
France, Japan's Fuji Speedway and the Higashi-Fuji Technical Center
in Japan. In fact, Fuji Speedway is the IS F's home circuit, and the
shape of turn one was the inspiration for the F-logo design.
The 2008 Lexus IS F will make an unmistakable design statement as
it launches the brand's F performance marque. The IS F applies a
distinctive new high-performance layer on the brand's L-finesse
design language, with themes and design features that set the F
model noticeably apart from standard Lexus models. Likewise, the
interior will feature exclusive performance-influenced luxury
appointments befitting the brand.
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.
"With Lexus solidly established as a luxury leader, it was time to
expand the brand's scope by offering unique high-performance
models, and the IS F is the first," said Dave Nordstrom, Lexus vice
president of marketing. "Lexus did not design the IS F as a direct
competitor to any specific models, but as a true performance sedan in
a distinctly Lexus way. The IS F is totally authentic with a unique
interpretation of driving excitement at all speeds and provides a new
definition of ‘usable power.'"
The Look of Performance Based 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.
The IS F's wedge-like profile is accentuated by functional front fender
air outlets with lower edges that transition into larger rocker panels
and continue as a character line into the rear bumper. The front
fenders wear a discrete silver, black and blue "F" marque.
The rear view conveys a strong parting signature for the IS F, with a
dramatic trapezoid shape and easily recognizable design elements.
Four exhaust diffusers, two per side in a vertical arrangement, are
integrated into the rear bumper. Above them, light-emitting diode
(LED) stop and tail lamps behind clear lenses give the IS F a unique
nighttime appearance. Attention to design detail extends down to the
white LED license plate lamps. The subtle rear spoiler is one of many
aerodynamic enhancements, which also include special underbody
panels to optimize airflow.
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 Engine, from the Bottom Up the 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, highperformance
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 V8 introduces new technology and features that are
exclusive to this version of the engine. Some of these include a dual
air intake system, engine-oil and transmission-fluid coolers for highspeed
performance and a cylinder-head scavenge oil pump. The
scavenge pump forces oil from the cylinder heads back to the oil pan,
ensuring a reliable oil supply even during cornering that exceeds one
g.
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.
Pistons use two-piece oil rings for low friction, and the skirt area is
resin-coated to reduce noise and vibration. The timing-sensor rotor is
attached at the rear of the crankshaft, which experiences less
vibration than the front.
Innovative Breathing High-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-tocylinder
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 lowpressure
port fuel injectors that help produce a precise burn to
optimize power and efficiency under light- and medium-load
conditions.
A dual air-intake system uses a primary intake passage for low and
medium engine speeds. In the higher engine speed range (above
3,600 rpm), both the primary and secondary passages are opened,
helping boost high-rpm power. Both intake passages share a common
high-efficiency, low-restriction air filter.
Lexus optimized the intake system down to the smallest details. For
example, the throttle valve shaft has been tapered down from 10 mm
to 7 mm diameter in the center to expand the intake air passage. The
intake manifold uses a simple plenum design with equal-length
runners.
High-Precision, High-RPM Valve Control With 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.
With the IS F 5.0-liter V8, Lexus has made a leap in valve-control
technology with the new Variable Valve Timing with intelligence and
Electrically controlled intake cam (VVT-iE). The exhaust camshaft
uses hydraulically controlled variable valve timing.
Variable valve timing systems typically use engine oil pressure to
operate cam-phasing mechanisms. In the IS F, using an electric drive
motor to alter the intake camshaft phasing made it possible to expand
VVT operational range to lower engine speeds, where engine oil
pressure is usually not high enough to operate conventional VVT. An
electric motor, with electronic control unit and a reducer, is mounted to
the front of each intake camshaft.
Dual single-row independent primary timing chains drive the intake
camshafts, which drive the exhaust camshafts via smaller secondary
chains. Reinforcement ribs inside the timing-chain cover reduce timing
chain noise, and integrating the water pump, oil pump and scavenge
oil pump into the timing chain cover reduces weight.
The IS F V8's compact pent-roof combustion chamber positions the
long-reach sparkplug nearly in the center. The plugs use an iridiumtipped
center electrode and a platinum-tipped side electrode. A water
jacket between the exhaust port and plug thread ensures optimal
cooling around the plugs. Four knock sensors in the engine's valley
reduce the possibility of detonation.
Supporting Systems A 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.
A number of additional engineering details were integrated into the IS
F to improve performance and efficiency. A cooling-fan motor was
installed that is 30 percent lighter than conventional fan motors, and
the fan shape was modified to enhance cooling and control noise.
Front engine mounts have liquid-filled insulators, and the rear mounts
are covered by rubber heat insulators. Inside the fuel tank, an offset
high-output fuel pump and a sub-tank help prevent fuel starvation
during cornering maneuvers. The alternator uses a larger front
bearing, a cooling fan and die-cast aluminum cooling fins for the
rectifier. The planetary-gear starter uses the crank-hold feature.
8-Speed Sport Direct Shift Transmission The 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.
The eight-speed transmission is approximately the same length and
width as the six-speed transmission used in other rear-wheel drive
Lexus models. The transmission has a die-cast aluminum case and
some aluminum internal parts, which contributes to weight reduction.
Using eight speeds allows gear ratios that maximize torque up to the
tire-grip limitations in the lower ranges while optimizing efficiency.
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.
In addition, a Sport mode switch on the dashboard allows the driver to
select from among Normal, Sport and Snow driving modes. In Sport
mode, the VDIM system allows higher dynamic thresholds before
intervening, alters steering assist to increase steering weight, and
throttle response is sharpened. With the transmission in D mode,
gears are held longer in response to throttle input.
Versatile Drive Mode When 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.
Until the engine reaches operating temperature, and when the VDIM
system detects slippery road conditions, the transmission will
automatically select 2nd gear start. Once the engine reaches
operating temperature, or VDIM detects better road conditions, the
transmission allows 1st gear start.
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.
Paddle shifting while in D mode, however, is not the same as in M
mode. If the vehicle is stopped, or if the vehicle is at a constant speed
for a certain period of time, the transmission will change back to
normal D operation. In addition, the driver can switch immediately into
normal D operation by holding the upshift paddle (+) for one second.
The transmission uses flex-lockup control and deceleration control
when decelerating while in D mode, using as many gears as possible
and extending the fuel cutout for maximum efficiency. AI-SHIFT
(Artificial Intelligence-SHIFT) complements the driver's Sport switch
selection by automatically adapting the shifting based on road
conditions and driver input. The new transmission is also highly
responsive to uphill/downhill driving, always selecting the best gear for
power or engine braking. Because the IS F is a Lexus, the intuitive
powertrain control optimally smoothes out off-the-line response.
Sporty Manual Mode Manual 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.
In 1st gear, the torque converter operates to provide torque
multiplication for consistent launches from a standing start. The torque
converter is locked continuously in 2nd through 8th gears to provide a
direct connection between engine and transmission for the fastest
shifts and most direct driving experience.
In M mode, gears will be held until the driver up- or down-shifts. Two
exceptions are if vehicle speed falls too low for the selected gear, then
the transmission will downshift automatically; and if the transmission
fluid or engine coolants exceed limits, then the transmission will revert
to automatic operation to prevent damage.
Shifts in 0.1 Second and Downshift Throttle Blipping New hydrauliccontrol
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.
The transmission-control system uses high-flow linear control valves
for engaging and disengaging the clutches. The resulting
simultaneous release and engagement of the shifting clutches
provides fast shifts while diminishing gearshift shock. The solenoids
allow direct control of the hydraulic pressure applied to the shifting
clutches, along with centrifugal fluid pressure canceling mechanisms,
enabling finer control than conventional clutch-control systems. In
addition to a conventional input-shaft speed sensor, the intermediate
members of the gear train use a speed sensor to allow finer control of
gear changes.
Driving enthusiasts pride themselves on the ability to execute a
perfect manual-transmission downshift, which requires "blipping" the
throttle while the clutch is disengaged to match the engine speed for
the lower gear. The IS F transmission executes perfect downshifts in a
similar way but with the consistency most drivers cannot match with a
manual transmission.
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.
To enhance performance and durability, a breather system separates
air bubbles from the transmission fluid during performance driving.
The transmission is also equipped with an air-to-liquid automatic
transmission fluid (ATF) cooler to help ensure optimal transmission
performance even during track driving. There is a transmission fluid
temperature warning-light in the instrument panel.
Sports Car Dynamics The 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.
Although using the basic double-wishbone front suspension and multilink
rear suspension configurations of the IS platform, the IS F benefits
from a multitude of track-proven modifications. The IS F sits an inch
lower on its suspension than the standard IS models, helping to lower
the center of gravity for quicker handling response. Like other IS
models, the IS F employs high-strength steel suspension components
for the optimal combination of rigidity and weight.
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.
Suspension bushings have been specially tuned for better feel, and
the subframe suspension mounts are stiffer than on other IS models to
help reduce sway and ensure control under acceleration and braking.
The engine mounts are also stiffer for a more direct feel. Special
jounce stoppers added to both the front and rear suspension come
into play early in the compression stroke to help reduce the roll angle
when cornering and to reduce dive when braking. High-rigidity hub
unit bearings are engineered for rigorous, high g-force track driving.
The Electric Power Steering (EPS) system has been remapped for
improved steering response and feel while providing precise control
and excellent straight-line control. The vehicle-speed-sensitive system
eliminates parasitic loss from a hydraulic pump and reduces weight
and complexity.
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.
The direct-type tire pressure monitoring system allows two sets of tires
to be registered, giving the customer the benefit of a system with a set
of track tires or winter tires. The multi-information display indicates the
tire selector switch.
Performance-Tuned Stability Control The 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 limitedslip
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.
In the IS F, a Sport mode switch on the dashboard allows the driver to
select from among Normal, Sport and Snow driving modes. In Sport
mode, VDIM allows higher dynamic thresholds before intervening and
alters steering assist to increase steering feel. Sport mode enables
optimal vehicle control on a track in areas where the skills of even toplevel
drivers are challenged.
The experienced driver can disengage VSC/TRAC by press-andholding
the TRAC-off button for more than three seconds. Even with
VSC/TRAC disengaged, however, the system still provides the brakebased
limited-slip differential effect and ABS.
High-Performance Brakes The 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 Lexus Passive-safety technology in the IS F begins
with a reinforced passenger compartment that helps protect the
occupants with front-and-rear crush structures. Seatbelt pretensioners
and force limiters are used for all seating positions.
In addition to the driver and front-passenger front airbags and front
seat-mounted side airbags, the Lexus Supplemental Restraint System
(SRS) includes side-curtain airbags that extend from A-pillar to C-pillar
and a knee airbag for both the driver and the front passenger.
Advanced dual-stage front airbags are designed to deploy based on
impact force. The driver's front airbag also includes an extra low stage
designed to deploy based, in part, on the seat's position on its track.
The front passenger's airbag features twin chambers, creating an
indentation in the center impact area that helps provide overall
occupant protection.
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.
The rear back-up camera, included with the available navigation
system, automatically projects an image of what its lens can detect
behind the car onto the navigation screen when the transmission is in
reverse gear. The available Intuitive Park Assist (IPA) system uses
ultrasonic sensors to detect objects close to the car's front and rear
bumpers, alerting the driver and showing distance to objects in the
multi-information display within the speedometer. When the IS F is
equipped with the navigation system, information on detected objects
is shown in greater detail on the seven-inch touch screen display.
Uncompromised Lexus Luxury Like the exterior, the interior of the IS F
features an exclusive design treatment highlighted by aluminized
composite trim, aluminum-rimmed main gauges, unique steeringwheel
treatment and other special surface treatments. The instrument
panel integrates a new oil-temperature gauge, voltmeter and shiftindicator
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.
In addition to the usual Lexus standards of comfort and convenience,
the IS F interior features specially shaped and trimmed seats that hold
the driver comfortably and securely in place. The special leathertrimmed
sport seats are available in Black with blue stitching or a
unique high-contrast Alpine and Black trim. The standard
SmartAccess keyless entry and push-button start allows the driver to
keep the access fob in a pocket or purse.
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.
The air conditioning system's electrically controlled variable
compressor adjusts output to demand rather than simply cycling on
and off. The system can independently adjust upper and lower
temperatures in response to ambient conditions or sunlight.
A multi-information display located in the speedometer integrates a
trip computer that provides outside temperature, driving range,
average fuel consumption, average fuel consumption since refueling
(per tank), current fuel consumption, average speed and the F logo.
The display also includes an oil-maintenance reminder and system
warnings.
High-Power, High-Performance Audio The 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 minijack
in the center console enables connection of an iPod® or other
portable music players.
Like all Lexus models, the IS F offers its own version of the Mark
Levinson® Premium Surround Sound Audio System, which is
specially tuned for IS F. This 14-speaker audio system features
discrete 5.1 multi-channel playback with 7.1-channel speaker
architecture. Its 10 amplifier channels provide 300 watts total output at
less than 0.1 percent total harmonic distortion from 20 to 20,000 Hz
(THD all channels driven). The Mark Levinson system plays
conventional CDs and DVDs, plus MP3/WMA-formatted CDs. DVD
movies can be viewed on the navigation system's color seven-inch
touch screen when the parking brake is engaged.

Lou
 
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