The strength of the BMW M4 Coupé is evident in every detail.
Jaguar has announced a raft of upgrades to its XF and XJ sedan models for 2013, including two new engines, a new eight-speed ZF gearbox, improved idle-stop technology, upgraded satnav and audio systems, and more.
Not your average nip-and-tuck, one might say.
In line with the industry trend towards downsizing and forced induction, the new engines are at the small end of the range, starting with the two-litre i4 turbopetrol, which uses a low-inertia turbocharger built into a thin-walled exhaust manifold to reduce turbo lag and make the installation more compact.
Jaguar quotes 177kW at 5500 revs, while chain-driven variable timing of both exhaust and intake valves maximises the spread of torque, delivering 340Nm from 2000-4000rpm.
But perhaps the most impressive number is 138.
That's the weight of the all-aluminium engine in kilograms.
This pint-sized powerhouse will take the XF from 0-100 in 7.5 seconds and on to 240km/h, says Jaguar, at a cost of 8.9 litres per 100km and 207g/km.
In the aluminium-bodied XJ limousine the quoted numbers are seven seconds falt, 240km/h, 9.3 litres per 100km and 216g/km.
The all-new three-litre supercharged V6 has independent variable cam timing and spray-guided direct injection, with the spark plug repositioned in the combustion chamber to place it in precisely the best position for efficient combustion, combined with a 10.5:1 compression ration, which is astonishingly high for a forced-induction engine, and a twin-vortex Roots-type supercharger mounted, American-style, in the vee of the block .
The result is a claimed 250kW at 6500 revs and 450Nm from 3500-5000rpm, accelerating both the XF sports sedan and XJ limousine to 100km/h in 5.7 seconds and on to limited top speeds of 250km/h. Both cars also return identical claimed fuel-consumption figures of 9.4 litres per 100km and 224g/km of CO2.
The 2.2-litre i4 Td turbodiesel is now available in two levels of tune: the entry-level variant delivers 120kW and 400Nm while the higher-powered version has been uprated from 140 to 147kW, with torque remaining at
Both the 175 and 202kW versions of the three-litre V6 Td in the XF now have an 'intelligent' idle-stop function, reducing fuel consumption to six litres per 100km and CO2 emissions to 159g/km.
The bigger (but lighter) XJ gets only the 202kW version, for which Jaguar claims the same numbers: six litres per 100km and 159g/km.
Jaguar's flagship five-litre petrol V8 - both in naturally aspirated and forced-induction format - also benefits from 'intelligent' idle-stop and eight-speed transmission.
ZF EIGHT-SPEEDER ACROSS THE RANGE.
The eight-speed ZF transmission that was introduced on the 2.2-litre i4 and three-litre V6 turbodiesel engines for 2012 is now standard across the XF and XJ ranges.
With a wider spread of ratios and more even spacing, the eight-cogger provides more seamless acceleration both from rest and when overtaking, while fuel consumption at high speeds is reduced.
Jaguar quotes a gearshift time of 200 milliseconds, whether in automatic or paddle-shift modes - although whether it has cured the heart-stopping hesitation on downshift that afflicts practically every paddle-shift transmission when barreling into a tight corner under heavy braking remains to be seen.
By using lightweight, compact components, including an aluminium differential housing,the weight of the eight-speed drivetrain has been kept the same as that of the six-speeder it replaces.
This is now standard in most markets on all diesel models, and V6 and V8 petrol engines. It shuts down the engine within 300 milliseconds of the car coming to a complete stop - at which point a green 'ECO' symbol lights up on the dashboard.
It follows a complex system of control algorithms that monitors a number of operational parameters including engine, ambient and cabin temperatures, whether the car is in fact standing dead still, and power requirements for ancillaries such as aircon and infotainment.
It's also able to restart smoothly in less time than it takes for the driver's foot to release the brake pedal and press the accelerator, by using a dual-solenoid starter that has its own battery to ensure in-car systems using power aren't affected.
It can even restart the engine while it's still running down, so you can grab a gap in the traffic without hesitation.
All XJ models now also have the recalibrated spring and damper tunes, providing enhanced ride isolation and occupant comfort, that was introduced on the range-topping XJ Ultimate for 2012.
All XF and XJ models have an upgraded touch scrteen with a number of new functions, including MP2 and MP4 capability for the optional TV tuner, and enhanced browsing functionality for the iPod interface.
The satnav system now has a 'ECO Route' option that uses the least fuel regardless of speed or distance. When the car approaches an intersection it automatically zooms in to make the upcoming route more obvious. It also uses a split screen to highlight the route when the driver approaches a junction where directional arrows are painted on the road surface.
The system can now also store 'Avoid Areas', and points of interest can now be downloaded and stored on the car's system from a USB memory stick.
SOUND AND FURY
All XF and XJ models are now optionally available with premium Meridian sound systems in either 380W or 825W format, each with multiple-channel amplifiers and digital signal processing software powering an array of loudspeakers.
The 825W system also has Meridian Trifield surround sound technology, with 15 audio channels feeding 17 speakers in the XF and 20 in the XJ.
Meridian's main claim to fame is that it doesn't measure the performance of its sound systems against its competitors but against the real thing, going into the studio to benchmark against professional singers and real instruments, to produce the most true-to-life sounds possible.
We're waiting on a reply from Jaguar Land Rover SA as to when the 2013 XF and XJ models will be released in South Africa.