The Fording of Jaguar--a multibillion dollar American adventure aimed at returning aggression and thoroughness to a mighty but moribund British marque--comes close to early blooming with this year's parade of XJ8 sedans.

Gone is that Venerable Bede of Jaguar power plants, a once gloriously polished, aluminum sculpted in-line six that over several decades devolved into a death wish.

In its place, a 32-valve V-8 designed and reared in England, with the exception of one crankshaft key from Detroit. It is superior by large gobs of muscle to the 245-horsepower six of yesteryore that, in its glory years, whenever out of the shop and momentarily exorcised of mechanical demons, was capable of adding considerable salt and vinegar to our travels.

Meanwhile, Jaguar's quite awful V-12 engine, a hangover from the old days and the majestic but heavy-handling XJS, has been condemned to extinction. Presumably buried at sea to perform buoy-mooring chores while assisting expansion of the Whitstable oyster beds.

The old four-speed automatic that never quite got it in terms of hunt, surge and hesitation whenever driver demands became, well, demanding, also has gone away. Now there's a thinking, five-speed ZF automatic, plus a Daimler-Benz transmission for the supercharged version of the XJ8. Both deliver sophisticated initial response and mid-range urgency that is "Masterpiece Theatre" in motion.

Steering and handling are no longer stiffer than Britain's infamous upper lips. There's a drive-by-wire throttle management system electronically coupled to traction controls that will tame the giddy slips and spins of Britain's national pastime: Bad-weather driving.

A simpler, lighter multiplex electronics system has banished Jaguar's primal electricals along with several hundred Lucas jokes. These cars will go 100,000 miles between plug changes, 10,000 miles between oil changes and a lifetime (yours or the car's) between timing adjustments and transmission fluid changes.

Consequently, reliability and durability--as measured by diminishing warranty claims and tall leaps in recent J.D. Power customer surveys--indicate that quality, value and thorough assembly have been exhumed from abysmal to precisely where they should be for a $55,000 luxury motor car.

Yet, as important as bad things ripped out, is the vital issue of what good things are left of the old XJ6.

Looks and lines, which in the past were about the only reason for owning a Jaguar, have been caressed without damaging the allure of the double grille and four-headlight nacelles, part of the XJ allure for 30 years. Interior leathers and woods are premium, and the craftsmanship of their assembly forms an interior that is fine furniture.

Above all, the Jaguarness of it all, the sense of personal elegance while traveling first class at extraordinary speeds, has sustained. Ford, blessedly, hasn't mucked with a nything proven. Just smashed the bugs. It has preserved a heritage and is actually making it better. Would that Ford could do the same with British cooking.

This new breed of Jaguar is actually a litter: four XJ cats replacing the XJ6 series. There's a standard-wheelbase XJ8, a long-wheelbase XJ8L, a super-luxury Vanden Plas and a supercharged XJR. Prices start at $54,750 for the base XJ8 and peak at $67,400 for the blown, high performance version.

Two engines are available. One is a 4.0-liter, aluminum-block V-8 transplanted from the Jaguar XK8 sports car. Breathing through its own nostrils, it develops 290 horsepower. Then there's the supercharged, intercooled engine of the XJR that was our test car. It is ventilated by an Eaton blower that helps snort out an incredible 370 horsepower. And that's a bunch more than even a Chevrolet Corvette.

Outside, what is basically a big, front-engine, rear-drive sedan doesn't get more tasteful than this. From a ple asantly abbreviated rear to a hood that rolls forward and down like some friendly prairie, distinction is with the very lightly chiseled edges of the passenger compartment and the voluptuous rounds of ends and silhouette.

The XJR is set aside from less snappy siblings by a self-assured look that is handsome with a whisper of menace. That's created by reductions of chrome around ends and the radiator, five-spoke alloys instead of much busier wheels on the XJ8s, and low profile Pirelli tires. Also a mesh grille that glances back to the saddle-tanked, wire-wheeled SS100 two-seaters of the '30s.

The new interior is elegant and charming, side air bags have been added, and many of the borrowings--such as a pillow-padded center console and a wood-faced oval for gearshift and radio and heater controls--are from the XK8 sports car. Superb leathers, places for stuffing stuff without making doors look like shopping carts, and thick insulation from outside dins produce a distinct sense of hushed privacy.

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Downsides. Instruments are buried deep beneath the dashboard cowl, making them difficult to read in a permanent gloaming. The wood trim is equally murky, and we'd suggest a quick return to the reddish browns favored by most everybody else in the luxury motor car business.

As there's a fractional lowering of the roof line, plus an expansion of trunk space with no change in overall length, big persons riding in the back will find their quarters and hindquarters scrunched and over-cosy. They'll be the first to yelp against Jaguar's claim that this is a five-passenger car.

But for you, the enthusiast, to heck with them.

For few motoring hoots quite match the distinctive rush of driving a Jaguar XJR and enjoying its powerful aplomb; of relishing the apparent paradox of a weighty, sedate sedan that, on command, becomes a four-door demon.

Hard acceleration will make the rear tires sing a song of torque and supercharging. None but the brave--with the exception of something like a Porsche Carerra or a Corvette--will glower at an XJR at a stoplight because it will swoosh to 60 mph in less than six seconds. Of greater importance, such pace is perfectly matched by the efficiency of the car's brakes, steering, chassis stiffness and suspension.

In the animal kingdom, a jaguar is one of the fastest things on four feet. In the concrete jungle, a Jaguar goes one better, as the quickest production sedan on four wheels.

1998 Jaguar XJR

The Good: The cat is back with supercharged performance, superior looks and quality. Credit Ford for this hands-off rescue of a tradition. Handles lighter, travels quicker and still offers distinction in a heavily uniform car market. First V-8 in the history of Jaguar, and well worth the wait.

The Bad: Rear seat room not among the improvements. Your call on whether extra performance and racier look is worth $13,000 above the price of the standard XJ8.

The Ugly: Murky woodwork brings gloom to sparkling interior.

Cost Base, and as tested: $67,400 (includes standard dual front and side-impact air bags; automatic air conditioning; audio system; cruise control; anti-theft engine immobilizer; telescoping wheels; power seats, windows and doors; five-speed automatic transmission with alternative sequential shifting; alloy wheels; anti-lock brakes with traction control; leather seats and wood trim).

Engine 4.0-liter, 32-valve, V-8 developing 370 horsepower.

Type Front-engine, rear-drive, four-passenger, high-performance luxury sedan.

Performance 0-60 mph, as tested, 5.9 seconds with five-speed automatic. Top speed, manufacturer's figure, electronically limited, 155 mph. Fuel consumption, EPA city and highway, 16 and 21 mpg.

Curb Weight 4,075 pounds.