2008 Lexus IS-F Preview

Performance sells, especially in the compact sports-luxury class. And for that class, factory tuner cars provide a showcase for the manufacturer's most serious commitment to performance. If the formula is simple - let the in-house hot-rodders loose on what is already a first-rate sports automobile - the implementation is not, and it has a positive effect on the rest of that automaker's cars, especially the all-important compact sports-luxury sedans, coupes, and convertibles.

For a start, the engine was developed in partnership with Yamaha. Nothing new there, as Toyota/Yamaha partnerships go back to the Toyota 2000GT of the late 1960s. The Yamaha engineers involved were last associated with the company's most recent Formula One engine effort, so they were well-versed in high-performance engine design and development. The block is die cast aluminum, with a forged steel crankshaft featuring mirror-polished journals for minimum friction. Connecting rods and pistons are designed and built for strength and durability in high-rpm operation.

The Yamaha-designed cylinder heads have a lightweight four valve per cylinder valvetrain with titanium intake valves, a dual-intake induction system that opens a secondary intake above 3600 rpm for more power, the SFI D-4 direct and port fuel injection system (similar to that used in other IS models) that allows a high 11.8:1 compression ratio for increased power and efficiency, and a new twist on the VVT-i variable cam phasing system. VVT-iE still uses conventional hydraulic control to "degree" exhaust camshafts - rotate the shaft relative to its static position to advance or retard valve timing and change valve overlap. Because this uses engine oil, which needs to be warmed to operating temperature and viscosity for the system to work, it doesn't operate when the engine is cold. To get by this problem, the intake camshafts are degreed by computer-controlled electric motors. The result is improved running from cold, increased power - and increased fuel efficiency and decreased emissions. Unlike some competitors, the IS-F will not come with a "gas guzzler" surcharge. Maximum power, all 416 horses worth, is developed at 6600 rpm, with maximum torque 371 lb-ft at 5200. Redline is 6800. And EPA mileage is 16 city, 23 highway.

If the engine is interesting, the transmission is even more so. Manual shifting is a necessity in a high-performance automobile, and high-tech high-performance these days means an automated manual gearbox, with lightning-fast up- and down-shifts controlled, along with the clutch, by electronic and hydraulic wizardry. Such gearboxes are found in all major road-racing series, and in many of the IS-F's competitors. They are not torque-converter automatics with manual shifting. Audi's twin-clutch DSG is the benchmark. Lexus challenges it with an eight-speed gearbox with a twist - it's both a torque-converter automatic in automatic mode, and fully manual in manual mode in gears two through eight. First uses the torque converter to deal with the stresses of starting, but it's locked up otherwise in manual, to provide a direct connection between the engine and transmission. Upshifts can take as little as one tenth of a second, with downshifts taking two-tenths. Engine and transmission revs are automatically matched during downshifting.

© Source: theautochannel
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Lexus IS-F Racing Concept

Tucked away at the Tokyo tuner show, details on this track version of Lexus's M3 rival remain sketchy. All we know is that it looks truly mean.

The massive front aero kit and rear spoiler hint that the racing IS-F could compete in Germany's DTM series. But the word on the show floor is that the car is nothing more than the pet project of IS-F chief engineer Yukihiko Yaguchi. As pet projects go, it's a good 'un.

In unrelated related news, we also hear that an IS-F will compete in this year's Super GT championship in Japan. That's the same series the awesome GT-R racer we saw earlier this month will enter, although the IS-F will compete in the GT300 class, not the Nissan's GT500 division.

Best of all, the IS-F GT300 is likely to be mid-engined, a revelation that Super GT officials have described as 'crazy' and we describe as a thoroughly good idea.

© Source: topgear
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Full Test: 2008 Lexus IS-F

Rather than shoehorning a 5.0-liter V8 into the nose of an IS 350 and simply calling it the IS 500, Lexus has instead cooked up a far more dedicated sport sedan with its new 2008 Lexus IS-F.According to Lexus, the "F" in Lexus IS-F is derived from Toyota's initial "Circle-F" designation of 20 years ago for what would become the Lexus brand itself. Circle-F later morphed into Flagship One or F1, which in turn became the internal code for the first Lexus car, the LS 400.

F Is for Fury
Regardless of what it means to the luxury carmaker (and how it appears to the serious sport-sedan buyer), the 2008 Lexus IS-F is a serious piece of highly engineered hardware indeed. At its heart, the 5.0-liter V8 (2UR-GSE) comes from a stroked version of the 4.6-liter engine (1UR-FSE) found in the luxo-cruising Lexus LS 460. Now that Yamaha (a frequent collaborator with Toyota for engine projects) has had its way with it, an essentially all-new engine pumps out an impressive 416 horsepower at 6,600 rpm with 371 pound-feet of torque available at 5,200 rpm.

Exclusive to this Lexus V8 are trick cylinder heads with solid lifters and titanium intake valves, plus a water-cooled oil radiator. There's also an oil-scavenge pumping system that keeps the engine supplied with life-sustaining lubricant even in high-G cornering, and even the fuel tank uses an offset pump in a sub-tank for the same reasons.

The engine's lightweight reciprocating mass (said to be half that of other UR engines) combines with variable valve timing to produce a lofty redline of 6,800 rpm.

There's an instantly recognizable pubescent change in the IS-F's voice at 3,600 rpm when the dual-path intake system opens the secondary plumbing (located in the right wheelwell), immersing the passengers in a furious symphony of eight-cylinder baritone.

When you pour the 5.0-liter V8's power through the highly modified eight-speed automatic transmission (from the LS 460), the 3,780-pound IS-F is good for a 4.8-second time to 60 mph on the way to a quarter-mile in 13.2 seconds at 109 mph, and it's still accelerating hard — very hard.

The price of the 2008 Lexus IS-F might make it persuasive. Though the official numbers won't be announced for a bit, Lexus says our estimate of $59,900 isn't "embarrassingly inaccurate," so we used the current IS 350's optional $2,550 navigation system price to calculate this IS-F's $62,540 as-tested price.

© Source: edmunds
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