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LateNight and PolarFox's Jaguar XJ Analysis ...


LateNightCable

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Before I delve into the analyisis, I will say, I think most everyone agrees that a Jaguar car should embody certain qualities. Feminine curves, and feline grace - Voluptous looking cars with a splash of glamour. So, I will judge the design of this new XJ on how well I feel it meets these criteria.

I don't mean to sound like a curmudgeoun or anything, but the design of the Bentley Continental GT, the last car I analyzed, and this new XJ are kind of crumby. But we will break it down to see what works, and what doesn't. -- LateNightCable

* Front ...

20029_jaguar-xj04.jpg

In the front view, we see the grill, which is a welcome reprisal of earlier XJ grills. But, it's rounded shape and the ovoid headlamps, which convey softness, seem at odds with the more squarish architecture of this new XJ which is giving off the opposite vibe. They seem forced, as if they were wedged into the design more for the sake of brand recognition, rather than as a more natural inclusion.

The lower bodywork blends seamlessly into the headlamps, which some would view as " integrated ", but I find it cheap and unfinished looking, made that way less for style, than for ease of production. The chrome strips on either corner also look kind of half baked. If the opening on the lower fascia were a more definate shape, and had some kind of break in the middle, it would tidy up, and " ground " the styling quite a bit.

* Profile ...

20029_jaguar-xj02.jpg

People just know the Jaguar XJ profile like they know the profile of the Porsche 911. Both being very destinctive. The XJ of the late 80's and early 90's was very square, but it's essential Jaguar look was preserved through it's profile. Sleek, low, with a sloping hood and tail. This new car possess none of that. The design is clearly focused on maximizing the practicality of interior volume, including luggage space. This is good from a purely practical stand point, but stylistically, it doesn't come across as very successful. In side view, it's a very chubby car, like an S or X-Type. But unlike those cars it lacks an elegant roofline to make the most of the situation. Follow the doorline with your eye towards the rear, and you see that the car actually gets thicker - a complete reversal of traditional Jaguar practice. I have always viewed Jaguar's lavish use of chrome as a mark of destinction, their decision to black out the pillars takes away so much, and is more in keeping with Ford than Jaguar. Even the XJR featured here, with it's blacked out window trim could use that destinctive Jaguar flash. The sloping tail has always been a important XJ cue, but in this iteration it's reduced to a stub. The upswept crease along the lower body " raises " the rear, but that is not what this car needs.

* Rear ...

20029_jaguar-xj03.jpg

The main issue I have with this back end are the taillamps, particularly the stiff outer edges. They have a very starchy, " pasted on " look about them. The rear deck is not nearly as sloped as in the past, so it needs to be " lowered " through other means. The license plate placed high on the boot lid is a mistake, as this simply " raises " the tail even higher. A lower placement would have at least given the impression of a lower tail. Also, the clear, squarish backup lights placed directly in the center of the taillamps is kind of odd. From this angle we can see the upswept crease along the lower body once more. Combined with the doorline, which is also slightly upswept, and contoured, it creates a rather awkward effect. There are too many creases going on attempting to slim this chubby XJ. It's a little busy.

In closing, looking at this car, I get the impression of two different worlds, that of Old World artistry and charictor, and that of Modern day practical concerns, attempting to co-exist, but with muddled results. " Jaguaresque " styling cues overlayed onto an otherwise traditionally shaped car. This new XJ may be a more " practical " design than any previous one. But stylistically I find it badly lacking that essential Jaguar verve.

" The new XJ is a luxury car with a true sense of gravitas. The proportions, stance and obvious dynamic quality clearly display that all important Jaguar DNA and give it real presence on the road. " -- Ian Callum, Director of Design

I don't happen to agree with you Mr. Callum, what you have come up with has neither the proportions, stance, obvious dynamic quality, or the real road presence of past XJs' or any real Jaguar. Go back to the drawing board.

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And on to the mechanics of the cat:

The Engine:

<img src=http://www.webcg.net/images/webcg/R000024455.jpg>

The Jaguar XJ is powered by the constantly updated AJ-V8. The AJ V8 is a Dual Overhead Cam V8 dating back to the XK's introduction. It is to date jaguar's first and only V8. For the new XJ, it has been bored from the original 4.0L to 4.2L. The engine features aluminum block and heads, and the two cyledner banks are angled 90 degrees apart. Each cylender has four valves, two exhaust and two intake. The demeanor of the AJ-V8 is every bit as silken as any mercedes or bmw V8, and it is technology on par.

The AJ-V8 comes in two flavors, naturally aspirated and supercharged. The naturally aspirated is a dynamic performer, it's broad and excessively usable torque curve is made possible by jaguar's VCP technology, or variable cam phasing, which is an infinately variable valve timing system. This engine is always the picture of well polished. What this motor gives up in low end torque to competitors from Lexus, Mercedes, and BMW, it gains in mid range flexibility. The Naturally aspirated form of the AJ-V8 produces 294hp at 6,000 rpms, a gain of only 4 off of the 4.0L unit used last year, and torque is up 13 from the previous motor to 303 ft/lbs at 4,100rpms.

The supercharged variant of the AJ-V8 forgoes the valve timing wizardry to dawn a helically geared Eaton Roots type supercharger blowing through dual intercoolers. This treatment makes this the Jaguar muscle motor. Last year's had a 4.0L version of this year's 4.2. The most important change to this engine was an addition for 2003 of a helically geared supercharger over a straight cut one. What is the difference?, the old Jag charged motors made a floor waxer-esque supercharger whine whenever revved upon, the new ones are totally silent. The thrust comes on low, strong, and suddently in the 394hp supercharged 4.2L motor, which finds peak power at 6,100rpms, torque peaks at 399ft/lbs @ 3,500rpms. This motor's long flat torque curve makes the Jaguar the most noticable thrustful car in it's class, as this supercharged engine uses a roots supercharger which is far less subtle about pinning you to your seat than the Lyscholm Screw-Type S/C or Twin turbo kit used by Mercedes, nor any naturally aspirated competitor. The supercharged XJR variant of the XJ is not for someone looking for an easy riding boulevardier, it is refined, but very muscular, and requires a sporting driver to be appreciated, for anyone else, the naturally apsirated motor is better choice of the two.

<img src=http://www.ebroadcast.com.au/ecars/Jaguar/PiCs37/2001XtypeEng.jpg>

Additionally, for certain markets, north america quite possibly to become one of them, use of the AJ V6 is planned, the AJ-V6, which was is a Ford Duratech V6, which has been retuned, and given such jaguar wizzardry as VCP, will make 240hp and 221ft/lbs of torque.This engine is a high winding motor with an amazingly flat torque curve, but it lacks the polish of it's german rivals, and it's sixty degree design seperates it from the 90 degree design used in traditional luxury V6s. The fact that it is 85% similar to the engine is a Ford Taurus however may be it's greatest downfall. Truly, the use of AJ-V6 on something so prestigious as XJ was a mistake.

Transmission:

<img src=http://www.canadiantracker.com/members/images/nacs2-TH.jpg>

This car comes with the increasingly ubiquitous ZF 6HP32 Six speed automatic transmission. Gearing on it is identical to that of the BMW 7 series and Jaguar S-Type, which is slightly tall. The supercharged motor pushes through the gears fast enough this isn't noticed, but the naturally aspirated motor feels very subdued by the gearing. The ZF is quick to downshift, and has a very tightly coupled torque convertor, making the best of the responsive jaguar engines. Last years models came with two transmissions, supercharged variants got a Mercedes-Benz 5spd automatic, naturally aspirated got a 5spd ZF auto, neither is as supple in shifting as the new 6spd ZF box. When driven calmly, this transmission/engine duo makes the big cat feel effortless, and keeps it silent, but have no fears, should you mash on the pedal, the tranny will find low gear, and the engine will be right there to pull on it. Like all jaguars before it, this one comes with their J-Gate shift mechanism, which is best described as wierd. Shifting this tranny as a manual is much more difficult than the more sensible layouts offered by other manufacturers, but it wouldn't be a Jaguar without it. On the upside, the new mechanism is considderibly more crisp than the last one, although the transmision software is very reluctant to allow the engines to reach their full revs.

The Jaguar puts its power to the ground through the rear wheels only, there is no option for all wheel drive, though traction control is standard, active stability control is an option. The Supercharged Jaguar is abrupt enough in the power department to make the XJR a handful in foul weather to the inexperienced driver.

Overall, the AJ-V8 powerplants are tried and true, and are well proven as reliable and sound, the ZF transmission is new, but has a strong showing, the driveline was a mere natural progression forward for the big car, it will offer no big suprises.

Chasis:

<img src=http://www.velocityphotos.com/images/stk/2004/jg2004xjr01.jpg>

Here is where the big cat sees it's greatest achievements and downfalls. The greatest achievement is the new all aluminum chasis. It's construction is now more airliner than luxury car, it's chasis is all riveted and bonded aluminum, which makes the big cat 60% stiffer than it's predecessor, and despite being well larger, is also over 440lbs lighter. This lighter weight adds a higher degree of performance yet to the XJ. As a result, jaugar is now working to get a network of body shops set up capable of repairing these alumium cars, as special traning and materials are neccesary. The new car is much larger, the traditionally cozy jaguar cabin, which some long criticized as tight has been replaced by one every bit as large as it's competitors, and a trunk to match. Unfortuneately, this moves the cabin forward, and makes the traditionally low XJ a much taller car. As odd as this may sound, those who enjoyed the crampt old XJs will miss it in the new one. Jag nuts everywhere know what i'm talking about. This new car seems to have germanic precision, british theme and diviergence, and american practicality in it's engineering. Whether it mixes well is yet to be proven.

The suspension

Up front, the XJ features a sports car like double wishbone assembly, which offers precise turn in characteristics, and the sharp and dynamic response that has come to be expected from these reflexive cats. The rear suspension, a multi-link design, is more for space savings than it is for handling. The multilink indapendant rear suspension offers a smooth and stable ride, which is bolstered by the new longer wheelbase, but the rear end does not have the solidly planted and precisely movable quality a double wishbown could have offered. The rear suspension will however, feature jaguar's air spring setup, which allows for self leveling, and CATS, a computer controlled 4 wheel adaptive suspension system, allowing the suspension to reset response and dampening dependant upon conditions.

A ZF-22 assisted power steering system will be used, it is a precise and well tuned system.

Performance:

XJR:

0-60 5.0 sec.

Quarter: 13.5 secconds

Top Speed: limited at 155mph

XJ8:

0-60: 6.6 secconds

Quarter: 14.4 secconds

Top Speed: Limited to 155mph

The verdict:

Easily the best large luxury sedan for the dollar. It's aluminum construction makes it light, and it drives more like a midsize. It is negligibly slower than the class leading S55 and S600 from mercedes, which are both 30-50k more expensive. The Jaguar does although, show they are compromising. The adition of an AJ-V6 powered model can do no good for the car's prestige, furthermore, such an engine has no place in the top of the line sedan. The cab forward archetecture and space saving rear suspension are trade-offs, they do take away some of the british character, but give you back a good deal of practicality. They have made a better car, it's just not the "no compromises" Jaguar XJ we've all come to love. It is easily the bargain leader of the segement, offering class leading performance and amenities for a very decent price, but in this, they have lost some of the big cat disregaurd for such things.

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