By Jim Meachen and Ted Biederman

In a perfect world, the 2016 Jaguar XJR high-performance sedan might just be the perfect car. It offers a wonderful blend of style inside and out, a luxury ambiance that is hard to equal at any price, the latest in information and safety technology, room for four discerning passengers, and the type of silky, powerful V-8 performance that will bring a smile to the face of even the most sullen person.

The Jaguar XJ — in whatever trim level — has a head-turning persona even though it's several years old in its current guise and it's as beautiful as the first day it hit the market. Jaguar designers have given the flagship sedan some styling tweaks for '16 including retouching a fractionally larger grille and reworking the air intakes in the front bumper. The headlights and taillights have been redesigned as well.

The interior is a luxurious combination of high-quality leather surfaces with chrome accents and elegant ambient lighting. Craftsmanship and materials quality rival any sedan on the planet. We found the front bucket seats wonderfully supportive. The rear seats are also extremely comfortable, but we discovered rear-seat legroom on the tight side in our standard-wheelbase model. We expect the available long wheelbase version will open things up enough for most people.

Cutting-edge electronics is dominated by a large touchscreen. The dash is awash in ice-blue lighting with the traditional Jaguar large round dials. But the dials aren't real, just clever digital representations that dissolve away into a huge picture of a Jaguar Leaper when the car is turned off. One of the truly magical features is the round transmission shift knob that rises out of the center console when the car is started and retracts when it is turned off.

Noteworthy is that the previous electronics interface has been replaced by Jaguar's new InControl Touch Pro System, which boosts a new quad-core processor and 60-gigabyte hard drive with the main interface being an 8-inch touchscreen. If you use a tablet or a smartphone, you will have some familiarity with the system. Icons can be rearranged and you can swipe between configurable pages. The new navigation system includes satellite mapping, pinch-to-zoom, and the option to put a map on the instrument display screen.

The XJR is loaded with standard equipment goodies that include an adaptive suspension, a JaguarDriver system with normal and dynamic modes, a panoramic sunroof, automatic xenon headlights, a power-closing trunk, rear-view camera, heated rear seats, front and rear parking sensors, and a blind-spot warning system. And the entire XJ line comes with what Jaguar calls "intelligent stop/start." It's improved from the version used several years ago, but unfortunately we are still looking for a totally unobtrusive stop/start system.

But when you take all the XJ goodness into consideration, it's the powerful supercharged 550-horsepower V-8 engine mated to an eight-speed automatic that really sets the R version apart from the rest of the clan. It has been measured in 3.9 seconds from 0-to-60 and 12.1 seconds @ 117.6 mph in the quarter-mile. It's what makes a perfect car for the perfect world. The smooth performance while negotiating a crowded highway awash in inattentive drivers — some who insist on cruising the left lane 10 mph below the limit — combined with the pristine comfort and luxury feel of the whisper-quiet interior is a truly rewarding motoring experience. The XJR also has the ability to stop quickly, measured at a scant 105 feet from 60 miles per hour.

Jaguar has a lifetime’s history of motorsports and this experience, combined with modern technology and innovation has created what some describe as a perfect blend of road, track and luxury. It’s particularly gratifying to whip the XJR around sharp curves and witness its effortless handling and experience the way it stays planted.

One caveat here, the exemplary winding-road performance does come at some small expense — in other words if you are expecting the plush ride of a traditional Jaguar XJ, you're buying the wrong XJ. We wouldn't call the suspension harsh, but it does have a solid feel with a certain measure of stiffness.

The Jaguar comes in standard and long wheelbase versions and in several variants — R-Sport, Supercharged, Portfolio and XJR trim levels starting at $75,395 for the 340-hp V-6 R-Sport. The top line XJR in standard wheelbase like our V-8 test car starts at $118,995, and $121,995 for the long wheelbase. And for the record it has an EPA rating of 15 mpg city, 23 highway and 18 overall. Our test car with a couple of options came in at $121,208.

Essentials
Base price: $118,995; as driven, $121,208
Engine: 5.0-liter supercharged V-8
Horsepower: 550 @ 6,500 rpm
Torque: 502 foot-pounds @ 2,500 rpm
Transmission: 8-speed automatic
Drive: rear wheel
Seating: 2/3
Wheelbase: 119.4 inches
Length: 202 inches
Curb weight: 4,134 pounds
Turning circle: 39 feet
Luggage capacity: 15.2 cubic feet
Fuel capacity: 21.7 gallons (premium)
EPA rating: 23 highway, 15 city, 18 combined
0-60: 3.9 seconds (Car and Driver)

The Good
• Outstanding acceleration
• Sumptuous interior
• Updated InControl interface
• Distinctive styling

The Bad
• All-wheel drive not available

The Ugly
• Backseat a bit cramped for large sedan