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Jaguar XF
Debut: 2007
Maker: Jaguar
Predecessor: S-Type |
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Launched at a critical time, XF is
probably the most important Jaguar in history.
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The new Jaguar XF is not
only
the last Jaguar developed under the ownership of Ford but it is also
the most important Jaguar in history. Because X-Type is set to enter
graveyard in one to two year's time, while the low volume XJ and XK are
unlikely to earn profit, the future of Jaguar will rely on the
middle-size XF, which is replacing S-Type as a British fighter to
Mercedes E-class, BMW 5-Series, Audi A6 and Lexus GS etc. If it is well
received by the market, Jaguar will be out of danger zone for the next
5 years. Otherwise, not even its new owner (expected to be Tata at the
time of writing) could save it.
Some background information first. Because Jaguar is short of cash, it
builds the XF on the same platform as the outgoing S-Type, which means
the same hard point positions (such as the same 2909 mm wheelbase) and
some common steel pressings. This saved development time and costs.
Another cost saving measure is to use conventional steel monocoque
chassis instead of the aluminum spaceframe originally planned. This
sounds disappointing to car lovers, but in my opinion it is probably a
correct decision. Remember, even the pricier Mercedes and BMW could not
afford the extra costs of aluminum spaceframe technology.
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Ian Callum bravely reinvented Jaguar's
design language. It is the first Jaguar breaking away from William
Lyon's theme.
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Using conventional steel chassis means it does not have any advantage
in weight compare with its rivals. In fact, being longer and wider than
others, it is also the heaviest in the class. For example, a 3.0-liter
XF tips the scale at 1679 kg, some 150 kg more than BMW 530i or 60 kg
more than Lexus GS300. However, it still undercuts its precedessor by
30 kg, thanks to the use of more high-strength steel in the chassis.
Looking from these photos, we can see Ian Callum's new design is
surprisingly pleasing. At first, you might find difficulties to accept
its thoroughly modernized looks. Traditional Jaguars penned by William
Lyon and Geoff Lawson were slim and classical. In contrast, Callum's XF
is sporty, muscular and sophisticated. Like most modern rivals, it
surrenders to the laws of physics and reshaped its waistline to rise
gradually towards a high-set tail in order to reduce aerodynamic lift.
From some angles it looks quite similar to Lexus GS – which is not a
bad thing – but with a steeply raked fastback, it looks even more like
a 4-door coupe. In fact, Callum wants it to look like a 4-door version
of XK. Also like the XK, it adopts a bonnet which pops up automatically
in the event of collision to provide enough clearance from the engine
hard points. This allows a sleek front end design while meeting
European pedestrian safety regulations. A smooth roofline and raised
tail contribute to a drag coefficient of 0.29.
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The "4-door coupe" look fits the image
of Jaguar very much. It's not a copy of Mercedes CLS either.
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However, the highlight should be the interior design instead. It gives
up the old-fashioned leather-and-wood approach and pursues a modern
feeling by using metallic effect as the main theme. This leaves woods
and leather as supporting roles. The materials and build quality is
perfect, matching the high standard set by Audi and easily leaving BMW
behind. When you enter the cabin, you may be surprised by its
simplicity – where are the air vents ? where is the gear lever ? Once
you press the START button on the transmission tunnel... A-ha ! Those
small covers on the fascia suddenly rotate to reveal the air vents,
while a rotary gear mode selector rises from the transmission tunnel.
At the same time, the dials on the dash illuminate, the trip computer's
LCD screen (located between the dials) turns on and the touch screen on
the center console comes into live. These gimmicks show a very
different Jaguar from what we used to know: it says modern, it says
high-tech, it says user friendly.
Space is a critical issue to the XF. The S-Type was infamous for a
cramped cabin even though it had the longest wheelbase in class. The
new XF is a little more generous, thanks to the use of thinner seats.
On paper, it even offers space comparable to its best rivals. However,
in reality most road testers still reported that the rear seats are
more cramped than others, especially headroom is limited by the sloping
roofline. Four 6-footers will be tight fit. The fifth passenger will
find his legs blocked by the large transmission tunnel.
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The biggest problem lies on here: lack
of rear headroom.
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The mechanical side is perhaps the least surprising, because XF shares
all major components with XK coupe, XJ sedan as well as its predecessor
S-Type - engines, gearbox, differential, subframes and suspensions.
There are four familiar engines: 2.7-liter twin-turbo diesel V6 (207
hp), 3.0-liter petrol V6 with dual-VVT and variable induction (240 hp),
4.2-liter V8 (300 hp) and 4.2-liter supercharged V8 (420 hp). All
engines mate with the excellent ZF paddle-shift 6-speed automatic with
Jaguar's shift program. As before, the suspensions consist of
double-wishbones up front and a multi-link setup at the rear. Although
they are basically the same as XJ and XK's, they have unique anti-roll
bars, knuckles and bushings. Again, CATS adaptive damping is standard
on the V8 models.
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XF is a good high-speed cruiser,
thanks to superb mechanical refinement.
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On the Road
No cars in this segment are perfect. Some suffer from firm ride (e.g.
BMW 5-Series on run-flat tires). Some suffer from mediocre dynamics
(e.g. Audi A6 and Volvo S80). Some suffer from lifeless steering (e.g.
Lexus GS). Some suffer from aging cabin (e.g. Mercedes E-class).
Perhaps the biggest problem is, most of them can hardly stir your soul.
Having seen so many executive sedans, you started feeling they are just
business as usual. To be different, you need to seek help from Italian
or British. If you cannot afford a Maserati Quattroporte, then Jaguar
XF could be the best answer.
We are not talking about figures. If we are, we shall find the Jaguar
very normal. It is neither the quickest nor the slowest in the class.
It provides neither the sharpest handling nor the softest ride.
However, if you combine all subjective aspects together, you will find
it unusually desirable.
Sitting in the driver's chair gives you the first unusual experience -
the view over the low dashboard and the sloping rear screen, cocooned
in a supportive seat, wide transmission tunnel, a sea of aluminum, wood
and leather and the interesting rotary gear lever... Jaguar
successfully lets you believe you are driving a premium coupe rather
than a mass market sedan. If Bentley Continental GT has a little
brother, then this could be it !
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Very few cars combine good ride and
handling as good as this one
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Start the motor - we are talking about the 4.2-liter normally aspirated
V8 - you will find a near-silent idle. Yes, this motor might be 12
years old, but it is still free-revving and refined by today's
standard. While it lacks bottom-end torque, it is compensated with the
best automatic gearbox in the world. As shown in the XK coupe, Jaguar's
own programming makes its gearshift slicker and quicker than other ZF
6-speeders being used by its competitors. The result is a perfectly
refined and responsive power delivery.
The chassis of XF is another source of joy. Jaguar's chassis tuning
maestro, Mike Cross, succeeded to bring a smooth ride and good handling
simultaneously. It feels like the sedan version of XK coupe - more
nimble than its size and weight suggested. Its cornering attitude is
neutral until a nice stabilizing understeer intervenes near the limit.
The suspensions (with CATS or not) keep the car stable in cornering.
The steering is precise, well weighted and, most important, the most
feelsome in this class. Therefore driving the big cat in tight mountain
roads is confidence inspiring. Overall, the handling lacks the
sharpness of BMW, but in return the Jaguar delivers better ride
quality, especially more absorbent than the German cars on B-roads. Its
cabin is also better insulated from suspension noise, tire noise and
wind noise. The XF is one of the few cars that is fun to drive hard and
relaxing for the rest of the time.
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Desirable ? Yes. But it needs better
base engines to drive sales.
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But the new Jag has its worry too. Among the four engines it offers,
only the aforementioned normally aspirated V8 excels. The
420-horsepower supercharged V8 might provide strong performance (say,
0-60 mph in 5.1 seconds) and stronger handling, but it can't match the
smaller engines' smoothness, quietness (consider that supercharger
whine) and steering feel. It is also very expensive. Most customers in
this class buy a 6-cylinder engine because it is cheaper to buy and
more economical to run. Unfortunately, the XF's Ford Cleverland V6 is
the weakest link. Just as in S-Type, it lacks both torque and
refinement. What a pity Ford could not invest more money into the
project.
This leaves the 2.7-liter twin-turbo diesel V6 to be the only credible
choice to most buyers. As shown in the XJ 2.7D, it is a remarkable
diesel engine, being gusty, frugal and especially refined. However, the
aluminum XJ 2.7D is 110 kg lighter than the XF 2.7D. Will this engine
pull the XF as well as its brother ? We can't tell until it go on sale
later this year. However, one thing is for sure: the diesel engine will
not be qualified for the USA market, so it is not going to be a savior
Jaguar would like.
Although we like the XF very much, it seems that its fate is already
decided. I hope I am wrong, but my sixth sense tell me even this good
car cannot save Jaguar. Good luck ! |
| The
above report was last updated on 6 Jan 2008. All
Rights Reserved. |
XF 3.0 diesel
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The best selling XF used to be diesel.
With the new 3.0D, it could get only more popular...
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In
Europe, the best selling Jaguar XF is actually the least powerful 2.7
V6 diesel. This engine is undeniably smooth and refined, but its 207hp
output is way below class standard. For example, BMW's 3.0-liter diesel
straight six produces 245hp in single turbo form and 286hp in
twin-turbo form. Audi's 3.0TDI V6 produces 240hp. Even the weakest
Mercedes 3.0 V6 makes some 224 horses. Remember, the steel body Jaguar
XF is a heavy car. It surely needs a more powerful engine to increase
sales.
Now Ford has upgraded the V6 to 3.0 liters. The engine block is still
made of compact graphite cast iron, but common-rail direct injection
has been upgraded to the 3rd generation, which utilizes high-precision
piezo injectors and 2000 bar fuel pressure to implement up to 5
injections in each combustion cycle. It complies with the next EU5
emission standard due 2011.
Two states of tuning are offered for the 3.0 V6. The base version
employs conventional VTG twin-turbochargers in parallel arrangement,
just like the old 2.7-liter unit. It produces 240 hp and 369 lb-ft of
torque. However, our focus is the high-power version, which uses an
innovative "parallel sequential turbocharger system" - Yes, both
parallel and sequential. What does that mean ?
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600 Nm of torque and 42 mpg economy...
do you still need petrol engines ?
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The
system has a big VTG (variable geometry) turbocharger and a small,
fast-reacting fixed geometry turbocharger. The big turbo basically
operates all the time. The small turbo joins it (thus works in parallel
to the big turbo) from 2800 rpm all the way to top end to provide full
boost. This arrangement is contrary to the two-stage twin-turbo system
of BMW, which uses a small turbo for low rpm and a big turbo for high
rpm (during which the small turbo gradually shuts down). Jaguar says
its system is superior to BMW's because the bigger turbo with its
larger diameter manifolds generates less back pressure than small
turbo, hence less pumping loss and lower fuel consumption. A big turbo
would have needed higher rpm to get into operation, so Jaguar opts for
a variable geometry turbine to solve this problem.
The result of this arrangement is 275 horsepower and an astonishing
600Nm, or 442 lb-ft of torque. This enables Jaguar to claim 5.9 seconds
for 0-60 mph. Yes, that means it is actually faster than the outgoing
4.2-liter V8 ! It is also the first performance diesel car built by a
British car maker. More amazing, at 42 mpg combined fuel consumption,
it is actually 12 percent more frugal than the old 2.7D. It sounds like
a dream come true !
On the road, however, the XF 3.0D S does not feel as fast as BMW 535d.
We suspect its 0-60 acceleration could actually take 6.5 seconds,
considering the lighter BMW claims 6.1. Nevertheless, this is still
very good for a diesel.
More impressive is how effortless its acceleration is. The parallel
sequential turbocharging system does not display any hint of turbo lag
at all. From a little higher than idle, it responds instantly to your
throttle input with mountains of torque, like a large capacity normally
aspirated V8. Furthermore, its power is delivered with a smooth and
quiet manner, just as refined as the old 2.7-liter engine. With this
marvelous engine, who still need others ? |
| The
above report was last updated on 26 May
2009. All Rights Reserved. |
XF 5.0V8
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2009 can
be called "Year of Engines" to Jaguar as two of its most important
engine families have been renewed. We have examined the entry-level
3-liter diesel V6. Now let us go through the new 5.0-liter gasoline V8,
an engine that accounts for most XF, XJ and XK sold in America.
Jaguar's AJ-V8 was born in 1996 in the first generation XK coupe. In
the beginning, the 4.0-liter unit already employed many advanced
features of the time, such as an all-alloy construction, Nikasil-coated
combustion chambers, quad-cam 4 valves per cylinder, intake variable
cam phasing and drive-by-wire throttles. This mean in the following 12
years it didn't need any upgrade bar a 200cc boost in 2002.
However, when it was installed in the new XF, which topped the scale at
some 1.8 ton, the 4.2-liter AJ-V8 started looking underpowered. More
precisely, it lacked the bottom-end torque of its larger capacity
rivals, such as the 4.8-liter BMW V8 and 5.5-liter Mercedes V8, so that
it needs to be worked harder to get the same pace. This hurt its
effortless manner. Therefore in early 2009 Jaguar finally introduced a
significant upgrade to the engine.
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Maximum output increases from 300 to
385hp...
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The 3rd generation AJ-V8 has its capacity enlarged to exactly 5000cc,
thanks to both larger bore (from 86 to 92.5mm) and longer stroke (from
90.3 to 93mm). Despite that, its efficiency is raised by adopting
direct fuel injection, dual continuous variable cam phasing, 2-stage
intake cam profile switching (which uses hydraulic-controlled 2-piece
tappets like Porsche's VarioCam Plus) and a 2-stage variable length
intake manifolds. As a result, maximum output increases from 300hp to
385hp, while maximum torque is lifted from 303 to 390 lb-ft. Torque
curve is also flattened. At the same time, fuel consumption is
virtually unchanged.
With the new V8, XF finally delivers a combination of effortless
performance and impeccable smoothness that we expected for a Jaguar.
0-60 mph now takes 5.5 seconds instead of the previous 6.2 sec. Good
enough for the company to abandon the supercharged SV8 model. Of
course, the 5-liter engine also gives birth to a supercharged version,
but now that engine will be reserved for the high-performance XFR.
Together with the new engine, Jaguar introduced a new generation
continuous variable adaptive damping system to replace its long-serving
CATS adaptive suspensions, which used to vary damping between hard and
soft setting only. All these improvements make a desirable car even
more desirable.
Next, we shall look into the flagship XFR. |
| The
above report was last updated on 26 May
2009. All Rights Reserved. |
XFR
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The new Jaguar motor suddenly makes
our favourite AMG 6.2-liter V8 almost too faint, too rev-hungry, let
alone BMW's V10...
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The
world of performance saloons has changed a lot during the past few
years. BMW M5, the long-standing champion of the class, has been
seriously challenged by its ever rising rivals, namely Audi RS6, AMG
E63 and CLS63 and Cadillac CTS-V. Each of them can be described as a
masterpiece in its own right. Unless you insist traditional qualities
like a high-revving power delivery, manual gearshift or endless power
slide, you are very likely to appreciate these cars over the M5.
The latest headache to BMW comes from Jaguar XFR. This is the successor
of S-Type R, which came close to beat the contemporary M5 seven years
ago. Compare with S-Type R, XFR is a vast improvement, of course, just
like any new cars compared with their predecessors. But let me make it
clear: XFR is in a better position than ever to challenge the top spot
of performance saloon league. There are a couple of reasons to support
my claim. On the one hand, the standard XF is already the most
desirable premium saloon in E-segment, as we have talked before. It
provides a solid basis that the S-Type just couldn’t match. On the
other hand, Jaguar has done a lot of development to the engine,
suspensions and running gears of the XFR, more so than its predecessor.
In my opinion, XFR is the most beautiful performance saloon currently
on sale. Unless Alfa Romeo decide to build one, I doubt anyone could
produce a design combining this level of taste and elegance, or
achieving a balance between sportiness and understated luxury so right.
Compare with it, Audi RS6 looks just too civilized, Mercedes E63 too
conservative, CLS63 too flamboyant and Cadillac CTS-V too rough, not to
mention the odd-looking M5. Because the regular XF is already so
beautiful, the R version needed only some functional tweaks to its
styling, i.e. larger air intakes, bonnet air scoops, a tiny rear
spoiler, slightly extended sills, quad-tailpipes and 20-inch wheels.
The only styling gimmicks are the chromed surrounds of brake intakes,
yet they only echo the style of center front grille.
Even fewer changes can be spotted in the cabin – apart from the deeper
bucket seats and a few additional switches on the dashboard, it is
basically the same as the standard XF. Which is not a bad thing indeed.
We still enjoy its clean design and fine build quality, and of course,
the sensational emergence of air vents and gear selector from sleep.
Even the cramped rear headroom appears to be more bearable for a car
with sporting intention.
The point of the car, however, is performance. Its power comes from
Jaguar’s new Gen III AJ-V8. Key features include a full 5 liters of
capacity (up from 4.2), dual-continuous variable valve timing (instead
of intake only) and the first direct fuel injection for Jaguar. On the
top of this, XFR added an Eaton twin-vortex roots-type supercharger,
whose aluminum rotors have 4 lobes to boost efficiency and reduce
supercharger whine, like Chevrolet Corvette ZR1. Thanks to the presence
of supercharger, it does not need variable cam profile switching and
variable length intake manifolds like the normally aspirated version of
AJ-V8. At 6500 rpm, it produces 510 horsepower – matching BMW’s 5-liter
V10 and AMG’s 6.2-liter V8, if not Audi’s twin-turbo 5.2 V10 or GM’s
supercharged 6.2 small block. Equally impressive is the torque curve,
which tops 461 lb-ft from 2000 to 5000 rpm. Moreover, at merely 1000
rpm there is already some 331 lb-ft of torque available for your
disposal. This mean it has bottom-end tractability to insult not only
the rev-hungry BMW M5, but also the naturally aspirated AMG cars. If it
can’t beat Audi and Cadillac, it won’t be far off.
For this application, the ZF six-speed automatic gearbox has been
programmed to make gearchanges 10 percent quicker than the standard
car. Other aspects of the car get similar shifts towards the sporting
side: 10 percent quicker steering rack, 27mm lower ride height, 30%
stiffer suspension springs and 1mm thicker anti-roll bars. XFR is also
benefited from the new continuous adaptive damping just introduced to
other XF. However, our favourite addition is ADC, or Active
Differential Control. This electronic limited slip differential
utilizes electric motors and multi-plate clutches to alter torque
distribution between the two rear wheels. For what ? To eliminate
understeer when you don’t want and induce oversteer when you provoke
the XFR into a power slide. By the way, among its rivals only M5 has an
active differential.
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The broad dynamic talents of XFR is
rare in the automotive world...
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On the
Road
The Jaguar motor does not impress initially. Although supercharger
whine is largely absent, it lacks both volume and sound quality to
match its rivals. However, this is also the only weakness of its
powertrain. Despite of weighing some 1.9 ton, the XFR's gigantic
low-end grunt overcomes its mass without the slightest hesitation. Its
0-60 mph claim of 4.7 seconds is proved to be conservative - Car and
Driver took only 4.3 seconds to do the same benchmark. If
our experience is anything to go by, European magazines should return
around 4.5 seconds including initial tire slip. C&D also timed 9.6
seconds to reach 100 mph. These figures proved that the big cat is on a
par with its German rivals, if not ultimately as quick as the more
powerful Cadillac
CTS-V.
However, what figures can't tell is how effortless such performance is
attained. Press the throttle pedal at just over idle speed, a strong
stream of torque is built up instantaneously as if it doesn't need any
rev to realize. The new Jaguar motor suddenly makes our favourite AMG
6.2-liter V8 almost too faint, too rev-hungry, let alone BMW's V10. As
a result, in the real world the Jaguar feels significantly faster than
both rivals. Both in-gear acceleration and overtaking surge are
superior. The smooth yet responsive ZF transmission works closely with
the supercharged engine to guarantee overtaking at minimum fuss.
The chassis of XFR is equally impressive. At first, you may be
surprised by the firmness in its ride compared with previous Jaguar R
cars. But with the aid of electronic adaptive damping, the XFR is well
damped and composed on undulation, far more supple than M5 and RS6. It
is nonetheless a good companion for everyday driving as well as
cross-country blast.
What really surprises is not its ride comfort or refinement, but its
handling. For a starter, the XFR has the best steering in its class,
being quick, precise and faithful. Then you will discover its chassis
is very well balanced, tightly controlled and composed when attacking
corners. Neutrality is its inherent merit, thanks to the endless grip
at front wheels. But once you are prepared to have fun, switched off
its DSC stability control and let its clever active differential to
take control, you can have access to a heroic, progressive powerslide
in M5 fashion - just easier to manage.
The broad dynamic talents of XFR is rare in the automotive world.
Compare with it, BMW M5 looks slow yet uncompromising and difficult to
live with. Audi RS6 seems dull to drive and seriously compromised in
the way it rides and handles. Mercedes' AMG duo appears to have
outdated chassis. Only Cadillac CTS-V stands a chance to match its
dynamic ability, which awaits a comparison test. However, the
Cadillac possesses neither the mechanical refinement nor the quality of
Jaguar, which is understandable for its lower price point. In terms
of E-segment luxury performance saloons, nothing comes close to XFR at
the moment. |
| The
above report was last updated on 30 May
2009. All Rights Reserved. |
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