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Jaguar XK
Debut: 2006
Maker: Jaguar
Predecessor: XK8 (1996)
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 From
E-Type, XJS to XK8, there was one common gene in their blood:
smoothness. No matter powered by straight-6, V12 or V8, these cars
never forgot to place smoothness at top priority – smooth engines,
smooth ride and smooth styling. They were the best luxurious grand
tourers of their time, not as sporting as German rivals but more
civilized and arguably more tasteful.
The latest XK wants to succeed this tradition. However, there are
plenty of changes made. First of all, its name has lost the letter “8”,
although it keeps the same 8-cylinder engine as its predecessor.
Secondly, its chassis and body have been changed to all-aluminum
construction, just like the XJ sedan. Thirdly, its suspension setup has
injected a fair degree of sportiness (to distinguish itself from Lexus
SC ?) but without going to the German level. Lastly but not least, its
styling signals a change of philosophy and the start of a new era to
Jaguar.
 We
start from the styling. XK is the first Jaguar designed completely
under the direction of Ian Callum. In other words, it finally leaves
the classical approach of the great late Geoff Lawson (see XK8, S-Type,
X-Type and most of the current XJ). You might remember Callum is famous
for designing Aston Martin DB7 and Vanquish, but since then he has not
had any masterpieces added under his name. Obviously, the hungry Callum
wants to set a new design direction for the next generation Jaguars,
but his first attempt seems haven’t won too many praises. Most people
found the new XK not as attractive as Henrik Fisker’s Aston Martin DB9
and V8 Vantage. Its lines are less sexy, its headlights are quite oddly
shaped and, horribly, its oval front intake seems coming from the
recycle bin of Ford (see the old Ford Taurus and Mondeo), although we
know Jaguar actually adopted that feature as early as the E-type.
 However,
we must appreciate his insistence of a low bonnet line, which was a
traditional feature of Jaguar. To comply with European pedestrian
safety law – which requires a substantial clearance between the bonnet
and the engine – most other car makers chose to employ higher bonnets,
which usually ruin the sleek lines of sports cars. Instead, Jaguar’s
engineers work together with Volvo’s safety experts to develop the
world’s first pop-up bonnet. During a collision, the bonnet pops up and
therefore creates a large clearance from the engine. It saves the
pedestrian and saves the style simultaneously.
The interior design is less successful. Ian Callum has never been good
at cabin design, and his weakness is shown in the new XK. Here is a
rather bland and characterless place. It lacks the classical theme of
traditional Jaguars and the elegant feel of Aston Martins. Instead, it
looks more like a Japanese or an American offering.
 However,
it is undeniable that the new XK is much better made than its
predecessor. The material is of high quality to shame 911 owners and
the fit and finish matches its price tag. It is also more comfortable
and practical than before. The driver will find more headroom and
legroom, thanks to a taller roof and extended wheelbase. Yes, the rear
seats are still dog seats, but this is not much a problem to its
customers – they typically own a Rover Range and a Mercedes S-class
beside the Jaguar GT. For two people, XK will be a fine place for any
journeys.
The chassis and body of XK is made of aluminum like XJ sedan. In other
words, most parts are made of extruded and cast aluminum. They are
bonded by rivets, adhesives and self-piercing screws. Although most
toolings share with XJ, it still costs thousands of pounds more than
conventional steel monocoques. However, from engineering point of view
the switch to aluminum construction is worthwhile - compare with the
old car, kerb weight has been down by nearly 100 kilograms to 1595kg,
undercutting BMW 650Ci (1640kg) and Mercedes SL500 (1770kg). At the
same time, torsional rigidity has been lifted by 31% to 30,000
Nm/degree. That’s even stiffer than Aston V8 Vantage and Ferrari F430 !
 The
lightweight is very crucial, because the new XK continues to rely on
the long-serving 4.2-litre V8 from its predecessor. This AJ-V8 has been
around us since 1996 when XK8 was born. Despite of its age, its
specification is still up to date: all-aluminum construction, Nikasil
coating on combustion chambers to reduce friction, quad-cam 32 valves,
variable valve timing on the intake side and drive-by-wire throttle.
This shows how advanced it was 10 years ago. Although its maximum power
and torque remains at 300 hp and 310 lbft, with 100 less kilograms to
pull it can shorten 0-60 mph to 5.9 seconds, while top speed remains
regulated at 155 mph.
Nevertheless, the 4.2-litre V8 can no longer matches its new rivals for
power and torque. For example, Maserati 4200GT produces 400hp and 332
lbft, BMW 650Ci kicks out 367hp and 361 lbft while Mercedes SL500 pumps
out 388hp and 391 lbft. They not only deliver stronger acceleration
than the Jaguar, but their superior low end grunt is obvious in regular
driving.
So what? The beauty of XK has never been hot-rod performance, but a
refined and relaxed manner. Unlike the aforementioned rivals, it is a
true luxurious grand tourer – the one that will cover ground quickly
yet comfortably. Undoubtedly, the new XK has a very good drivetrain
combo to fulfill this task. Its AJ-V8 is still very smooth and refined;
its ZF 6-speed automatic transmission is also a source of joy. In
automatic mode it shifts seamlessly. In the paddle-shift manual mode (a
new feature of the car) it responds so quickly and matches the rev so
well.
 The XK
also rides and handles very well. The starting point is a rigid yet
lightweight chassis. Base on that are suspensions derived from the XJ
sedan. They got rid of air springs but retained the CATS adaptive
damping. The tuning is sportier than the old XK8 but not to the extent
of BMW 650Ci.
 At first,
you will feel it rides harder than the old car, but as speed rise the
damping gets increasingly beautiful. Obviously, the suspensions are
much more absorbent than the German and Italian rivals, and the driver
feels much more relaxed when cruising in the XK.
At the same time, the new XK displays a vast improvement in handling.
Its steering manner is agile, willing and neutral. Its tires generate
tremendous grip. Although it rolls more than 650Ci and the ABC-equipped
Mercedes SL, it is not a shame for a luxurious grand tourer, and is a
big improvement from the bulky XK8. The only real problem is a steering
that delivers no much feel from the road. However, neither BMW nor
Mercedes are truly feelsome.
This mean the XK is a good luxurious GT. It has refined engine and
drivetrain, superb ride, capable handling and fine build quality to
deliver what its customers demand. What it lacks is desirability. Quite
unbelievably, the missing link comes from Ian Callum’s exterior and
interior design. |
| The
above report was last updated on 13 Apr
2006. All Rights Reserved. |
XK Convertible
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 The
convertible version is very important to the sales of XK, as
traditionally this kind of version contributes to half of the sales of
the segment. However, the conversion from coupe to convertible is not
as brilliant as Porsche and Ferrari did to their cars. Although Jaguar
claims the chassis of XK Convertible is 60% stiffer than its
predecessor, at 16000 Nm / degree it is only half the value of the XK
Coupe. As a result, it lost some finesse in ride and handling when
being pushed hard. Moreover, the Convertible’s windscreen design does
not contain wind buffeting very well. In short, the Coupe is the XK we
want. |
| The
above report was last updated on 13 Apr
2006. All Rights Reserved. |
XKR
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 If
the naturally aspirated XK is good, then the supercharged XKR must be
very good. At £68,000 in the UK market, it is just £8500
more than the base version but it offers 120 more horsepower and 103
lbft more torque. It carries only 70 more kilograms than the XK, so
0-60 mph is shortened by a full second to 4.9 seconds. Such kind of
performance elevates it above Mercedes SL500 (SL550) and BMW 650Ci. It
is not as fast as SL55 AMG and M6 though, but those cars cost
£97,000 and £82,000 respectively, so XKR represents good
value for money.
Outside, the XKR distinguishes from its lesser model by mesh grilles,
bonnet vents, quad exhaust pipes and a slight restyle to front bumper.
That's enough to catch attention and raise your pulse. Inside, the
bland dashboard is again the weakest link of the car - it will surely
need an early makeover.
 However,
the ugliest part of XKR is not the cabin, but the engine: the 4.2-liter
all-aluminum 32-valve supercharged V8 is completely hidden under a
black plastic cover, which must be the ugliest engine you have ever
seen. It may be good for noise insulation, but I am sure everybody will
prefer to see the real face of the mechanicals rather than a plastic
pseudo engine. Take note, Ian Callum.
The engine itself is close to the XK's
and even closer to the last XKR. An Eaton supercharger is added to
boost power to 420hp at 6250rpm (that's surprisingly more revvy than
the naturally aspirated version) and torque to 413 lbft at 4000 rpm. In
other words, only 20hp and 5 lbft more than the old car. Luckily, the
all-aluminum car is 70 kg lighter than before, so a couple of tenths is
slashed from 0-60. Yes, it is not as explosive as M6 and SL55 AMG, but
for a grand tourer the supercharged AJ-V8 engine is close to perfect:
smooth, responsive, torquey and good sound. The supercharger whine is
largely reduced, letting the nice exhaust noise to take the leading
role. The latter is more civilized than Aston's, so perfectly suitable
to Jaguar.
 The ZF
6-speed automatic programmed by Jaguar is currently the best automatic
in the world. In automatic mode it shifts seamlessly yet slightly
quicker than in the XK. The program detects your driving mood and
select the right gears. For example, if you are driving hard it will
hold the gear until higher rev or downshift earlier so that to enhance
acceleration. During a downshift it will blip up the engine to match
rev. In manual mode it responds instantly to driver input through the
steering wheel-mounted paddles. No other automatics could be so
satisfying to keen drivers.
Although the aluminum chassis of XK coupe is already very rigid, Jaguar
still added a tower brace to reinforce its rear suspensions. The
springs in suspensions are stiffened by 38% up front and 26% at the
rear. The CATS adaptive damping is recalibrated to 25% firmer. The
anti-roll bars becomes thicker. The steering becomes quicker. The
brakes are also enlarged.
 On the
road, XKR won overwhelming praises from journalists all over the world.
Many German grand tourers work better on track than on public roads,
which is nonsense considering their drivers will never took them to
racing tracks. But XKR is vice versa. It is a real grand tourer
designed for real roads, no matter highway or back roads. Its handling
is excellent for a grand tourer. It has remarkable poise, neutrality
and grip. Its torquey engine and responsive gearbox adds to the feel of
integrity. But most impressive is how well it deals with rough surfaces
simultaneously. No German grand tourers know how to soak up bumps
better than Jaguar. It flows smoothly from bend to bend. The fluidity,
refinement and effortless performance are exactly what great GTs
required.
For handling and feedback, the big
Jaguar is still no match with the nimble Porsche 911, or to lesser
extent Aston V8 Vantage. But from grand tourer point of view, no one
else is more satisfying to drive. My only reservations are about its
design - which is so-so now and easily aging in the future - and the
cheap-looking cabin. Image-wise, Jaguar still has a thing or two to
learn from Mercedes SL. The latter also has a superior retractable roof
to justify the higher price.
However, there is no doubt that XKR has finally evolved from a lazy cat
to a jaguar. |
| The
above report was last updated on 16 Sep
2006. All Rights Reserved. |
XK and XKR 5.0
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The XKR still combines speed, control
and refinement like no others...
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Having
read our new XF 5.0 and XFR report, it won’t be difficult to understand
the new XK and XKR 5.0. Under the limelight is the Gen III Jaguar
AJ-V8, now enlarged to a full 5 liters and is equipped with goodies
like dual-continuous VVT and direct injection. In naturally aspirated
form, it also gets 2-stage variable intake valve lift and 2-stage
variable length intake manifolds. Output jumps to 385 hp and 390 lb-ft,
nearly matching the old supercharged engine. 0-60 mph is dramatically
reduced to 5.2 seconds.
The 5.0-liter supercharged XKR is even stronger – 510 horsepower
instead of the previous 420 hp, 461 lb-ft of torque against 413 lb-ft,
0-60 mph is reduced by 0.3 second to just 4.6 seconds. 0-100 mph dips
below the once-supercar-defining border of 10 seconds. Mid-range
acceleration is even more sensational, which sees 50-70 mph taking 1.9
seconds instead of 2.5 seconds. XKR is a 911 killer.
Apart from performance, the big cat also inches closer to the 911
territory in handling. A change in tuning philosophy means it has
sacrificed part of the previous supple ride and impeccable refinement
for a sportier character. The suspension springs are considerably
stiffer. The new continuous adaptive damping (which replaced the
2-stage CATS) and electronic active differential (standard on XKR)
sharpen its handling a lot, bringing tighter body control and keener
turn-in. Although the suspension could be caught out by poor surfaces
at times, its ride quality is still better than other German and
Italian
grand tourers on the market. The XKR combines speed, control and
refinement like no others.
Externally, the 5.0 cars are refreshed with a pair of vertical brake
intakes at either side of the front bumper. Certainly more elegant than
the original design. Inside, Jaguar has no budget to redo the ugly
dashboard, but it has applied upgraded materials and XF’s rotary gear
selector to brighten things up. |
| The
above report was last updated on 10 Jun
2009. All Rights Reserved. |
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