by : Joe Wiesenfelder
July 9, 2008
Since the 1980s, German luxury automakers BMW and Mercedes-Benz have sold thrilling high-performance, higher-priced versions of their models with M and AMG designations, respectively, such as today's M3 and C63 AMG. Audi has followed suit with S and RS versions, such as the S4 and RS 4, and Jaguar offers R versions, such as the XKR. A few years ago Cadillac threw its noodle into the alphabet soup with the CTS-V, the first of a growing V-Series. Now, 18 years after raising the Lexus flag in the U.S., Toyota's luxury brand has scrounged up an unused letter, F, to represent its hot wheels. The first car to get F'd up is the compact IS sedan — currently sold as the IS 250 and IS 350 — resulting in the 2008 IS-F. (See the three trim levels compared side-by-side and check out the accompanying video for some of the cosmetic differences.) More F versions are sure to follow.Lexus' first attempt is worthy of the competition, but it cries out for a manual transmission, and it has a few quirks that prevent it from besting the class leaders.
Cosmetic exterior changes are always part of high-performance packages. BMW and Mercedes-Benz have always taken a more subtle approach, as does Audi with its S lineup. However, Audi has a newer souped flavor, RS, and the resulting RS 4 is more showy than the S4. Against this backdrop, Lexus seems to have taken more of an RS approach with the IS-F, adding wider fenders; a deep, flared bumper with a larger mouth flanked by virtual funnels to route cooling air to the brakes; vents behind the front wheels; and a high-domed hood. These items serve a purpose, managing airflow and making room for the larger, taller engine. It really is a tall engine, requiring a power dome so high that the IS-F's profile evokes a beluga whale. Definitely the most beluga-looking car since the 1999 Buick Riviera.
An admirable exercise in restraint, the IS-F's tail has a trunklid spoiler so modest it could easily go unnoticed. (I suppose Lexus could offer an enormous wing ... in an option package along with zit cream.) Quad tailpipes, in two stacked pairs, are a nice touch. Similar to the LS 460's, these finishers are affixed to the bumper and spaced an inch or so from the ends of the actual dual exhaust pipes — not directly attached. The exhaust blows through the tips, but they're not a continuous piece.
The car sits 1 inch lower than the regular IS, and the prominent side sills and 19-inch wheels add to the ground-hugging appearance. The regular IS has 17-inch wheels standard and 18-inchers optional.
Where the IS 250 and 350 have V-6 engines, the IS-F mirrors the BMW M3 and Mercedes C63 AMG in powering the rear wheels with a large V-8. The 5.0-liter produces 416 horsepower at 6,600 rpm and 371 pounds-feet of torque at 5,200 rpm. Lexus claims there was no target or benchmark during the IS-F's development, but its 2 hp superiority over the M3 is unlikely a coincidence. The IS-F differs from the M3 in that it doesn't offer a manual transmission, though it is the first car in this class with an eight-speed automatic (yes, eight) adapted from the LS 460. It operates in fully automatic mode and can also be shifted manually using the gear-selector lever or aluminum paddles on the steering wheel.
The IS-F's power delivery is a bit peaky for a V-8, with respectable but unexceptional acceleration at low engine speeds. Then the tachometer hits midrange, and before you can say "Where's the torque?" the pipes are blasting out a glorious V-8 roar and your internal organs get pancaked. The only problem with the exhaust note is that it's elusive, brought about through some variable combination of rpm and load that I was never able to predict, then utterly vanishing when you let off the gas, likely reduced to a frequency only other whales can hear.
For what it's worth, the tame torque at low rpm keeps the drive wheels from losing traction upon launch and probably keeps gas mileage in check, though you wouldn't know it from the car's 16/23 mpg city/highway rating. I found the M3's power more consistent: Though it's no bottle rocket off the line either, and its maximum torque is substantially less at 295 pounds-feet, it peaks at a comparatively low 3,900 rpm — and on a car with a redline of 8,400 rpm, that's still in the bottom half of the rev range. The IS-F's redline is a more typical 6,800 rpm. I tell you, the way some larger-displacement engines are being tuned these days, they feel like they have more turbo lag than some actual turbocharged four-bangers do. Still, 0-60 mph in less than 5 seconds commands respect.
Eight speeds is a lot — enough, I would think, to give the IS-F a faster launch. Once I got past the transmission's notable gear count, I wasn't overly impressed with it. Its claim to fame is that it can shift in one-tenth of a second, according to Lexus. Though this "direct sport-shift transmission" seems to be as fast as the dual-clutch automated manuals that have been introduced lately, most recently in the M3, the Lexus is more of a conventional automatic.
The advantage of automated manuals is that they have the efficiency of a direct, mechanical coupling and typically lower weight than traditional automatics, which use fluidic torque converters. The best of the automated manuals use a separate clutch for the odd and even gears, which allows them to upshift with lightning speed. (Single-clutch versions, found in the Smart car and BMW's erstwhile Sequential Manual Gearbox, are the appalling example of why you need two.) Lexus attempts to achieve the same ends by speeding up the shifting and locking the torque converter in all gears except 1st. (Torque converter lockup in higher gears is actually pretty common in automatics nowadays, and is partly responsible for their improvement in efficiency over the past 10 years.)
When you stand on the gas in the eight-speed's fully automatic Drive or Sport modes, it absolutely snaps from one gear to the next almost instantaneously. It's when you're already in motion and/or applying measured pressure to the accelerator that it sometimes exhibits lag and indecision. The clutchless-manual mode is decidedly unsatisfying. To be clear, I'm known for proclaiming that shifting via Dumbo ears is one of the sillier things a driver can do, but even I can tell good paddle shifters from bad.
When you're really heavy on the gas, the right-hand — upshift — paddle usually triggers a quick response. Likewise, the left-hand paddle effects a quick throttle blip and deft rev-matched downshift. Technically, the transmission shifts quickly, but that doesn't mean the initial response time is always good. It's at its worst when you shift by more than one gear. Downshift from, say, 7th to 5th or 4th gear, and it steps through each one rather than hopping directly. The same is true of multiple-gear upshifts. Flick the "+" paddle three times, and you go from 2nd to 3rd to 4th to 5th. I don't think it matters if the handoff from one gear to the next is a tenth of a second — or a hundredth — if you have to wait a half second before it happens ... three times in a row.
Get up to highway speed and put it in 8th gear, as indicated on the instrument panel, and it holds in that gear. Even if you stand on the gas, it won't kick down. I think this is the way it should be, but I was flummoxed by the transmission's refusal to upshift when I apparently wasn't going fast enough. As you accelerate, you flick the plus paddle, and maybe it will jump to the next gear, and then again maybe it won't. If you're not going fast enough, it doesn't respond. So what do you do? Keep flicking until it responds? All the way up to 8th gear? I spent way too much time doing something I never do in a real manual: wondering what gear I was in and whether I should — or even could — be in some other gear. People who think six gears in a real manual transmission are overkill just don't get it, but I'm thinking eight speeds is overkill when in sequential-manual mode. In automatic mode, the more the merrier.
The shift paddles are mounted to the steering wheel, which is simply the wrong approach for this configuration. If you're going to use separate downshift and upshift levers, they should be on the steering column so you always know which one is where, regardless of wheel position. If you prefer your flappy paddles on the steering wheel itself, they'd best be twin push/pull types so it doesn't matter where the wheel is turned so long as you can get at one.
The IS-F has three drivetrain modes, selected via a switch inconveniently located on the dashboard in front of the driver's knee, where it can't be seen behind the steering wheel. The default drive mode maximizes efficiency and smooth shifting. Sport makes the accelerator pedal more sensitive, raising the rpm at which shifts occur. Honestly, I'm not sold on the increasingly common practice of varying the throttle progression because I think this is an area where consistency is better and safer.
There's also a Snow mode that basically does the opposite of Sport — making the pedal less sensitive and keeping the transmission in as high a gear as possible to minimize wheelspin on slick surfaces. It's well worth having with rear-wheel drive, though the car comes with summer performance tires, which would be a raw deal in winter. All-season tires aren't an option. Though you'd have to purchase them on your own, Bridgestone now sells Blizzak winter tires in the correct sizes at roughly $265 a pop, according to TireRack.com. All-wheel drive, which can be had on the IS 250, isn't available on the IS 350 or IS-F.
Equipped with six-piston front and two-piston rear brake calipers with large cross-drilled discs, the antilock brakes have plenty of stopping power, but they're a touch grabby and there was a period where mine were squeaking. (Maybe Lexus has captured the German gestalt after all!)
For its firmed-up suspension and low-profile tires, the IS-F's ride quality is pretty good. It isn't quite as comfy as the M3, which all of our reviewers praised as exceptional.
The handling is good, but not without fault. Body roll is well in check, and the IS-F begs to be thrown hard into corners, but it feels nose-heavy to me. Lexus cites the front/rear weight distribution as 54/46. A little bit of understeer bias is a safe characteristic, but the IS-F pushes more than I like. You can balance things out by sending more power to the rear wheels, but this can reveal another shortcoming, and that's the rear-end traction. The tail gets squirrely very easily, and though a little sideways driving is to be expected in a rear-drive car with this much power, I found the degree excessive. The Bridgestone Potenza tires perform well in the general sense, which leads me to question if the rear rubber is just too narrow. To focus solely on tire size is to oversimplify, but it raises suspicion that the IS-F's rear tires, at P255/35R19, are the same width as the regular IS' optional tires and only 10 mm (that's less than half an inch) wider than the standard tires. The front tires, rated P225/40R19 on the IS-F, are the same width across the model line.
I suppose I should entertain the notion that a larger rear spoiler would provide more downforce and help keep the rear end planted ... wait, is my face breaking out? I think I'd rather spin off the road daily than drive around with a ski jump on my trunklid.
The IS-F uses brake-based traction control, which acts quickly to keep wheelspin from getting out of hand. In lieu of a mechanical limited-slip differential, Lexus says, the traction control keeps power going to whichever wheel has more traction. Now, the traction control can be turned off, using a button next to (and potentially mistaken for) the obscured Sport/Snow switch, but Lexus says the lateral torque transfer always operates. The same applies when you defeat the electronic stability system, which you do by holding the button for several seconds (when at a stop). In my experience, the traction control turned itself back on after reaching a certain speed. The stability stays off.
I can't say definitively that a regular mechanical limited-slip differential would mitigate the squirrely rear end, but, again, everything's suspect. My concern with traction control is always that it will be compromised under the most demanding conditions, like competitive driving, by brake fade.
As for the steering, it uses electric power assist, which is increasingly common because it's more fuel-efficient than the hydraulic type. Of its kind, the steering is good, but it still doesn't match the best conventional power steering; here the M3 has an edge in weighting and feedback. (Theoretically, electric assist is more variable and controllable with speed and other factors, but I've yet to experience one that lives up to its potential.)
Distinction isn't easy to accomplish in this copycat business, but Lexus succeeds in the IS-F. A defining element is the trim on the center console and doors — woven silver strands that look like a cross between aluminum and carbon fiber. The blue that highlights the F badges on the outside carries over in the form of blue gauge needles and blue stitching on our car's black leather surfaces. (Alpine white seats are another option.) There's even a hint of blue emanating from the perforations in the seat leather. Of course, the F badges themselves are here, too, on the steering wheel, the custom instrument panel and on the sides of the seat cushions, front and rear. I don't remember seeing that before.
Apart from the controls hidden behind the steering wheel, the ergonomics are pretty good — aided because Lexus has resisted the move to multifunction controller knobs like BMW's iDrive. The optional touch-screen navigation interface is a bit dated, but it beats the heck out of the typical German offering. The backup camera has no lines superimposed to show where your fenders are, but it's still good to have this feature. Our car also had front and rear sonar parking sensors, a $500 stand-alone option.
The front sport seats are very comfortable. I overheard another reviewer saying, "All cars should have seats like that." I'm not quite as effusive, but I do think they were a good combination of comfort and support, with side bolsters that hold you in place without crowding your shoulders or hips too much.
Where the regular IS has a three-passenger backseat, the IS-F has only two seats. I have no problem with this because the center seat is usually worthless anyway, but I can't figure out why Lexus went with a hard black plastic console between the two. The flip-down center armrest is fine, but what underlies it is low-rent. The woven aluminum must be pretty expensive.
To put it mildly, the rear seats are snug, with roughly 1 inch more headroom than the M3 sedan but 4 inches less of critical legroom. The regular IS 250 and 350 are no better; they're somehow harder to get into than the backseat of some two-doors. The seats don't fold down to extend the trunk space into the cabin.
In addition to the required frontal airbags, the IS line has knee airbags and side-impact torso-protection airbags for both front occupants. Side curtain airbags protect the heads of front and backseat occupants in a side impact. Where most cars have seat belt pretensioners for the front seats only, the IS has them for the backseat, too.
I left the IS-F with a déjà vu of a déjà vu — recalling how I wished the 3.5-liter IS 350 had a manual transmission like the IS 250 does ... which made me recall wishing the IS 300 had a manual transmission when it made its 2001 debut. To be fair, the IS-F's transmission isn't bad; bad would describe the BMW Sequential Manual Gearbox — now being phased out — which I flatly recommended against. I think the average automatic driver could get into the IS-F, drive all day and never think twice about its transmission. But this isn't a car for the average buyer. The person who plunks down $56,000 for a car with this one's appetite for gas is serious about performance, and denying that buyer a manual transmission only casts klieg lights on whatever you offer in its place.
Eight speeds or not, the IS-F's transmission needs work, and the rear end needs to be tamed. The IS-F has plenty of appeal, but in terms of all-around performance, it doesn't quite stand up to the BMW M3. At $56,000, its list price is $2,200 more than the BMW. The M3's optional dual-clutch automatic adds $2,700, but that version still has the edge, even if you want an automatic.
source : www.cars.com
