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Lexus IS-F Full Details

November 12th, 2008
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For 30 years, Yukihiko Yaguchi has been a man on a mission - to build a vehicle he would want to drive, love to own and would stir the emotions of all that experienced it.

The result of this ambition is the IS F: a vehicle that delivers exceptional performance and handling, is engineered to inspire and yet holds true to the Lexus values of being built to the highest levels of fit and finish.

Yaguchi is an enthusiast, a performance hard-case who loves to drive fine, responsive equipment.

In his time at Lexus, Yaguchi has worked on the first and second iterations of the Lexus LS luxury sedan, the turbocharged Toyota Supra and the first Lexus GS sport sedan.

During this time Yaguchi pitched several ideas for a performance-inspired vehicle, with little success.

So in 2002, tired of waiting, Yaguchi decided he'd bypass official channels and figure out a way to build it.

Yaguchi was ideally placed to start such a project, working at the Lexus Center in the Brand Strategy department in preparation for the global expansion of the Lexus brand.

The first struggle he faced was that in Lexus' careful planning, it's not the engineers who make the decisions to design and develop a vehicle - it's the Product Planning Department.

Yaguchi pitched his concept to Product Planning. After much convincing, he received Product Planning's approval to proceed.

But just because the project got the green light that didn't mean it had resources and budget allocated to it, so he began working on the project informally, on the side, beginning in 2004.

Yaguchi had effectively begun his own special "Skunk Works", an under-the-radar operation in which he recruited a team of driving enthusiasts and engineers who, working in their spare time between their regular assignments, developed their own vision for a Lexus performance vehicle.

Working outside the confines of Lexus' usual carefully planned corporate program, Yaguchi cherry-picked the very best people - individuals he thought would want to have a hand in creating this special car, as opposed to having to.

As the project gained traction and grew so too did the development team, but unlike most projects which typically have between 1,500 and 2,000 people working on the development, Yaguchi had between 100 and 300 people at any given time.

So to combat the lack of manpower and development resources, Yaguchi called on many favours and contacts within Lexus and TMC to assist with the vehicle.

Names such as Yamaha, Brembo, Bridgestone, BBS, Toyota Technicraft (responsible for the SC 430 GT cars) became involved with the project.

In the case of Yamaha, Yaguchi asked for assistance from his old friend Mr Kimura, who worked on Yamaha's Formula One engine program and was general manager of the aftermarket project division.

As a result of that request, Yamaha did most of the development on the IS F's DOHC 5.0L V8, making sure to pack it with more than 311kW of power, enough to propel the IS F from 0-100km/h in 4.8 seconds.

The overall result is an engineering marvel, with an outstanding engine, excellent aerodynamics, Brembo brakes that feature huge, 360mm cross-drilled discs and six pistons per caliper up front, 19-inch wheels, a specially tuned suspension system, an eight-speed Sport Direct Shift transmission with paddle shifters and its own special performance profile.

Eventually the project became so well known, and Yaguchi's persuasiveness so legendary, that the whole experience came to be known as Yaguchi-Go.

In Japanese "go" is a suffix referring to a car, but originally it characterised a ship, the equivalent of a vessel making its unstoppable way forward.

So this was Yaguchi and his project cutting a swathe, and leaving a wake, through Lexus.

In this way, "Yaguchi-go" constitutes recognition of his leadership, and ownership, of the IS F project.

But Yaguchi's development goals didn't stop at project partners, but extended to the development.

Key to his concept was that the IS F should be just as capable on the road as a racetrack, so he selected what is arguably one of the world's most infamous race circuits, Fuji Speedway, for evaluation, testing and final tuning.

In fact, there's never been a Lexus production vehicle that has been so heavily tested - with confirmation testing conducted at Nürburgring in Germany, Paul Ricard in the South of France, Belgium's Circuit Zolder and Laguna Seca in California.

The true measure of the importance of Fuji lies in the name of the vehicle - with the 'F' symbol derived not only by name, but also shape from the speedway from which the vehicle was born.


Lexus' premium performance vehicles will bear the "F" symbol, derived in name and design from Japan 's Fuji Speedway - the home of Lexus performance vehicle development.

The "F" symbol is more than just the first letter of its namesake - it also depicts the first corner of Fuji Speedway - commonly known as 27R.

"F" vehicles have been designed for driving enthusiasts and bring a new level of performance and enjoyment to the Lexus range.

The first Lexus vehicle to bear the badge in Australia will be IS F sports sedan.

Lexus Australia's Chief Executive John Roca said IS F signalled the expansion of the Lexus range outside its traditional luxury vehicle segment.

"IS F is the embodiment of performance," he said.

"Just by looking at the vehicle you know that it is something special. It is the ultimate in performance sedans and Lexus' first performance-specific model.

"Much as the LS 400 did in the luxury market, IS F will challenge performance rivals in its field - providing a level of performance and on-track ability unlike any previous Lexus.

"In a nation that worships its performance sedans, the IS F will tickle the senses of all enthusiasts, whether they are behind the wheel, passing the car on the street or just hearing it rumble by," Mr Roca said.


Standing in the shadows of Mount Fuji , the 4.56km Fuji Speedway is regarded as one of the world's most spectacular and challenging race circuits - but it is more than just a circuit to Lexus.

Originally designed in 1963 as a NASCAR-style circuit, it later morphed into a race circuit with a banked race section - which proved to be extremely testing on both vehicles and competitors.

Fuji Speedway was then redesigned to incorporate a new section around the banked curve and in 1976 played host to its first Formula One Grand Prix.

The famed circuit saw completion of a three-year remodelling project in 2005, the return of Formula One in 2007 and, more importantly, formed the gruelling test bed for the development of Lexus performance, or "F" vehicles.

The telling link between the track and Lexus is the development of the IS F - everything from the IS F's handling to braking and overall performance was honed at the testing circuit.

The result is a Lexus that has been designed for driving enthusiasts, bringing a new level of performance and enjoyment to the Lexus range.

Lexus is firmly entrenched at Fuji , with the company's global training facility housed onsite.

Lexus Fuji College was opened in March 2005 as a Lexus-exclusive training facility to develop the human resources, dealers and hospitality necessary to provide unparalleled after-sales service and purchasing.

The college offers a program of courses on customer interaction as well as product briefings directly from chief engineers and designers.

Fuji Speedway at a glance:

Length: 4,563m
Width: 15-25m
Right corners: 10
Left corners: 6
Straights: 8
Longest straight: 1,475m
Maximum Incline: 8.88%
Maximum decline: 10.05%
Total area: 76,000m2

Number of circuits: Five (Fuji Speedway, short course, drift course, gymkhana course and karting course)

For years Lexus has stood for superior ride comfort, innovation, refinement and whisper-quiet vehicles.

The launch of IS F adds a new element to the Lexus brand: passion.

IS F will bring to the brand a host of new customers - those with a passion for vehicles, driving and most of all; the ownership experience.

"The performance market is unlike any other market Lexus operates in, there are no clear demographics," said Lexus chief executive John Roca.

"Performance vehicle purchasers do so based on emotion and feeling.

"For a long time, Lexus vehicles have been chosen on their merit and those that have done so have never regretted the decision - but with the IS F, we add emotion," said Mr Roca.

"There are customers out there who view Lexus as the butler of the luxury market: quiet, reliable, polite and well groomed. They would consider a Lexus, but want excitement from their vehicle.

"The IS F is their vehicle - it has Dr Jekyll and Mr Hyde personalities within it.

"Day to day, it can be as quiet and refined as you like, but on the track or a good road, the IS F rewards all of the senses," said Mr Roca.

"We will be marketing this vehicle in a totally different way - in effect, you could say the IS F is everything you thought we weren't."

Lexus IS F has new suspension hardware and a performance-oriented suspension calibration.

In addition to its new suspension, it has additional underbody aerodynamic aids - to increase negative lift.

The new suspension calibration includes higher-rate coil springs, larger diameter monotube dampers, thicker stabiliser bars and larger wheels and tyres - compared with the calibration for IS 250.

The larger diameter monotube dampers have an internal assist spring and a varying diameter laminated valve - to provide accurate turning of the damper curves.

The dampers also have a free piston with increased gas pressure - to reduce the chance of damper fluid cavitation.

The urethane-bound stopper on the front suspension strut has been redesigned to act earlier in the compression stroke.

It works in conjunction with the new, stiffer springs to reduce cornering roll and dive during braking.

The larger-diameter stabiliser bars increase roll rigidity and optimise the vehicle's roll posture.

In addition, IS F has new, stronger hub bearings, to optimise reliability in circuit driving.

IS F's suspension hardware includes aluminium uprights (front hub carriers/rear stub axles), to minimise unsprung weight.

The new Lexus IS F 5.0-litre Quad-Cam V8 engine has an intelligent electrically controlled, continuously variable valve timing system on the intake camshafts.

The electric inlet camshaft actuation system - known as Variable Valve Timing - intelligent Electric, or VVT-iE - improves engine performance and fuel efficiency, as well as reducing emissions and engine vibration.

The IS F engine also has intelligent variable exhaust camshaft timing, with hydraulic activation.

The dual VVT-i system is designed to continually optimise intake and exhaust timing, according to engine load, temperature, revolutions and throttle position.

It offers benefits across the engine revolution range, including increased low-end torque and higher top-end performance - the latter by making optimum use of the 'breathing' advantages of valve overlap.

Lexus dual VVT-i also contributes to a significant reduction in exhaust emissions, such as oxides of nitrogen (NOx) and hydrocarbons (HC).

Lexus developed electrically controlled VVT-i to provide additional benefits and greater valve timing control.

Hydraulic VVT-i cannot operate below 1000rpm or when the engine is cold.

However, the VVT-iE system will operate across the full engine revolution and temperature spectrum, with a cam response speed of some 50 degrees per second in the retardation phase and 150 degrees per second in the advance phase.

The Lexus 2UR-GSE engine in IS F has a range of 40 degrees of inlet camshaft timing variation (relative to crankshaft angle) and 35 degrees of exhaust camshaft timing variation.

It can vary valve overlap (the period when both the exhaust and inlet valves are open) from a minimum minus 10 degrees to a maximum of 65 degrees.

The IS F inlet cams have 248 degrees duration and the exhaust cams have 244 degrees duration.

The Quad Cam 2UR-GSE engine has separate primary cam chains to drive the inlet camshaft in each cylinder head, and secondary chains to drive the accompanying exhaust camshaft from each inlet cam.

Lexus now offers dual VVT-i engine technology in eight models.

The new-generation dual VVT-i Lexus Quad-Cam engines meet the previously conflicting goals of:

improved torque at low revolutions, and

better use of the expansion ratio in the cylinder and exhaust pulsation to improve engine breathing at high revolutions.

The dual VVT-i system boosts torque at both low and high engine speeds.

It makes full use of exhaust pulsation to increase cylinder filling at high rpm.

The engine ECU controls camshaft advance and retard, via electric motors for the inlet camshafts. It controls exhaust camshaft timing via an oil control valve mounted on the cylinder head and vane-type actuators on the ends of the exhaust camshafts.

In addition to its dual VVT-I, the new IS F engine has dual injection, with both port injection and direct injection.

There are five main dual VVT-i operating scenarios.

Engine idle: inlet camshaft neutral position, exhaust camshaft on full advance. This eliminates valve overlap, thereby reducing volume of exhaust gas blowback into the cylinder and inlet ports - for stable combustion and improved fuel economy.

Low engine speed range with light to medium load: inlet timing is retarded and exhaust timing is retarded for increased overlap. This creates two parallel effects: increased internal exhaust gas recirculation rate to reduce oxides of nitrogen and re-burn hydrocarbon, and reduced pumping losses and hence improved fuel economy.

High-load range, low-to-medium engine speed: inlet timing is advanced to close the intake valve earlier, reducing the volume of intake air blowback into the inlet ports and improving volumetric efficiency.

High-load range, high engine speed: inlet timing retarded, exhaust timing advanced. Retarding the inlet timing (according to the inertial force of the inlet air) improves volumetric efficiency and hence power.

At low temperatures: Retarded intake timing and exhaust in the full advance position, to eliminate valve overlap to the intake side. Fixing the valve timing at extremely low engine temperatures - and controlling the range as the temperature rises - stabilises fast idle and improves fuel economy.

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