Alpina B7 vs Audi S8 Plus vs Jaguar XJR

Something is not quite right here. Each of these three-box designs has four doors and four seats, ostensibly providing elegant family transit for the very well-to-do exec.

But then you hit the starter button, and all three musketeers drop their masks. Dominating the stage now are three mean V8s, each assisted by two fat turbos or a growling supercharger, always eager to rev and with legs long enough to gobble up blacktop in time-warp fashion.

Attached to the boosted V8s are eight-speed transmissions with wham-bang upshifts, and chassis wearing broad-shouldered tyres, bratwurst-diameter anti-roll bars, aggressive brakes employing discs as large as small satellite dishes, and steering boxes which aim, more or less successfully, to fuse intuition with inspiration and information. Styling varies from the gothic to the technoid, through to the neo-baroque, with each individual cockpit nevertheless embodying an arcane mix of sports bar and cigar lounge.

Bang for buck is not the point. After all, upkeep and depreciation would feed a central African village for the better part of a year. True, if you applied fake 3.0-litre V6 badges to the relatively inconspicuous Jaguar you might just about quarantine it from the rage of the envy-driven. But even if the Audi were sprayed in boss’s teeth yellow, and the BMW Alpina painted taxi beige, neither would fool wealth spotters for longer than the blink of an eye.

If you are eyeing-off any member of this trio with serious intent, then what you want is not mere opulence and efficiency with a handy turn of speed. Any of these cars makes a statement. You want one because you want the best of breed, a wolf in sheep’s clothing with the pace and class to run unchallenged at the forefront of the pack.

Since the middle of this year, Audi has aspired to that place with its enhanced S8, the S8 Plus 4.0 TFSI quattro tiptronic. A 4.0-litre, direct-injected, twin-turbo engine brings you 445kW and 700Nm, driving all four wheels via an auto-locking central diff to push the two-tonne saloon to 100km/h in a claimed 3.8sec, and on to a maximum of 307km/h on unrestricted autobahns.

That makes the $330,216 Plus the fastest S-car Audi has produced, however irrelevant that may be on any road in Australia now the Northern Territory has reintroduced speed limits. And it puts it 63kW ahead of the un-enhanced S8, which like the S8 Plus is based on the D4 A8 platform introduced in 2010.

For those prepared to trade some unnecessary pace for an elevated position from which to argue – perhaps over a port – about how understatement counts towards class, an alternative of similar vintage to the Audi has been available from Jaguar in the XJR. For about $300,275, Jaguar’s ultimate limousine supplies you with 404kW and 680Nm from a supercharged 5.0-litre powerplant, driving the rear wheels only to a 4.5sec 0-100km/h time and a top speed of 282km/h.

The newest entrant to the V8 uber-limousine contest has the credentials to take on this pair strength for strength. Alpina has long been absent from Australian showrooms but it made a return late 2016, initially offering B3 four-door and B4 two-door models based on BMW’s 3 and 4 Series cars and built to order.

The German performance marque has had a five-decade relationship with BMW that roughly parallels the connection HSV has developed with Holden, producing high-performance versions of BMW vehicles with characters subtly or not-so-subtly different from those defined by the donor brand, and with the willing and early cooperation of BMW engineers.

Melbourne-based importer the In Motion Group recently confirmed it has completed homologation for the 7 Series-based B7 Bi-Turbo. Pricing is not yet confirmed, however given the 750Li on which it’s based retails at $312,700 we wouldn’t expect much change from $400,000 for our third and newest contender.

On paper, the much fresher BMW B7 is the car to beat. The Alpina treatment includes bespoke turbochargers, a free-flow induction and exhaust system, and a small army of intercoolers, oil coolers and radiators, pushing the output of the 4.4-litre twin-turbo BMW V8 to 447kW (a giant leap from the 330kW of the original).

Add 800Nm at 3000-5000rpm and you get a top speed of 331km/h and the ability to roar from rest to 100km/h in 3.7sec – making the B7 comfortably faster than the Audi and a tenth quicker too. Self-discipline is key to putting any of these club-lounge rockets to the test, and this Alpina needs an empty autobahn or a local police force on vacation to demonstrate its talent. On a country road, it could destroy your driving licence in a blur of speed and precision driving mechanics.

The untold mission of the Alpina flagship, with its trademark ’70s-look multispoke wheels, is to show BMW and the world that no one does super-luxury sports sedans better than the small Bavarian specialist. It represents an attempt to unite the finest of all worlds as the ultimate common denominator of comfort and performance. The 7-Series chassis combines all-wheel drive with rear-wheel steering, makes adaptive adjustments to the anti-roll bars, and links the adaptive dampers to a camera that scans the road ahead.

The B7 impresses in many areas, but there are three traits we don’t like. The squat under full-throttle acceleration from low to medium speed kicks up the bow and feels very old-school. Brakes compensate for a shortage of initial bite with subsequent vigour and pronounced dive. And the steering on less than perfect turf transmits too much information. No big deal, but a couple of small bruises on an ego transferred from maker to machine.

The longer-matured Audi and Jaguar do without the B7’s innovations, and they too complete the morning’s cross-country run with more than a few ruffled feathers. Take for instance the dynamic steering of the S8, which feels artificial, is too light, and declines to self-centre as swiftly and progressively as you would wish.

When you give the Audi stick at the exit of a bend, the body likes to bob up and down once before the car settles for the straight-ahead. And the tiller’s calibration is confusingly broad. Around town, a quick two-finger flick at the wheel gets you round any 90-degree bend.

On the freeway, however, the set-up is almost too stiff even for high-speed stability freaks. Drive Select invites you to dial in a slightly more relaxed steering action – or an alternative that is even more frantic.

The Jaguar XJR is a low-tech pussy-cat by comparison with the others here: no AWD, no RWS, no four-corner air suspension, no assistance systems overload. The 2016 model brings a few new balls of wool to the table however, such as electronic support for taking off on slippery surfaces, dubbed ASPC (for All Surface Progress Control), and electro-mechanical steering.

Whenever you are no longer in the mood for low-rev, sheathed-claws wafting, simply hit the Dynamic button and the Jaguar will duly morph from living-room pussy to snarling wild cat. It has the most likeable steering of the lot, packing a sweet blend of input and response, quick turn-in followed by nicely weighted feedback, with enough interest as you wind on more lock yet zero nervousness to encourage second guessing when carving a straight line.

There is some unwelcome momentary stiffening during quick left-right-left manoeuvres though, and the helm feels constantly compelled to make slight self-adjustments – not because one needs them, but because the beast within has decided them necessary. What this wild feline does not like at all are undulations, transverse ridges and recurrent surface changes, where it keeps picking fights that can deflect its path.

The Alpina soaks up vagaries more comprehensively than the grip-oriented yet latently tail-happy Jag and the lightfootedly neutral Audi. In combination with a unique Sport-Plus mode, the special software developed in house will send only 10 per cent of the torque to the front axle, lower the ride height, select the tautest damper setting, switch the steering to flick-quick and turn up the exhaust volume.

On mirror-smooth tarmac, that’s the way to go. But on bumpy ground, one should mix and match the settings. Although it is 5250mm long, rear-wheel steer makes the B7 feel almost as nimble and agile as a 5 Series. The absolute stopping power leaves little to be desired, but we would still prefer compound discs for even more strength and stamina.

The S8 Plus is the deceleration king. It musters carbon-ceramic rotors (front only), which combine the bite of an angry doberman with the relentlessness of a whippet and the attention of a German shepherd. Negative deceleration is such a forte that one soon starts to push the Audi to its ABS-monitored limit. In terms of handling prowess, it is quite easy to induce a trace of lift-off and power-on oversteer, which should be fun in the wet.

The stoppers fitted to the Jaguar are more obliging and easier to modulate but no less tenacious. Being the only rear-drive contender, the XJR is in principle favourably disposed toward the odd smoky burnout and a whiff of sideways pathos. But at the end of the day, we found it more rewarding to mastermind the momentum, to position the car for the next corner, and to keep up the flow.

Ergonomically, all three models strike an odd balance between brilliance and madness. This applies in particular to the Alpina, which should come with a half-day total immersion course. Autonomous driving? Yes, but not in this vibrating, beeping and flashing please-wait-another-four-years manner.

Touch and zoom, push and turn? Sure, but not all at once – and be careful with your gestures, or gesture control may turn the radio on full volume when you had sought merely to soothe an itch. Although the S8 still is the quality leader and materials champ, its cockpit feels less intuitive than it used to feel. How come?

It’s the curse of doing things because they can be done, plus an erratic gear-lever which drives you bananas when selecting R or P, and persistent difficulties penetrating the callous Multi Media Interface maze with your digit. Nor is the Jaguar a master of the centre stack. While the latest infotainment system does bring it up to speed, the busy steering-wheel, the scattered controls and the distant touchscreen are nothing to brag about.

The Jaguar mixes eight parts XJ with two parts R. It’s a four-seater GT, brawny but dated. The Audi is the sports car in this trio. The S8 Plus is sure-footed, corner-greedy and charmingly competent. The Alpina treatment has turned the 7 Series into a much faster yet barely less docile hyper-sedan. Even though ambition and ability don’t always match, the Alpina B7 does outperform the competition.

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