Audi S4 vs BMW Alpina B7

What's the difference?

The S4 and S5 range continues to represent a great formula for performance you can live with every day. They're arguably the sweetest balance Audi produces, actually. All come fantastically equipped, with cabins that feel truly special, and we’re lucky they can be had in a choice of five bodystyles.  

The BMW Alpina B7 is a special car destined (like all Alpinas) to be a collector's item, due to its rarity and exclusivity. I asked Alpina just how many current model B7s there are in Australia and the answer was "less than five", which is just as mysterious as most people find the car in general.

The B7 is fast – too fast to enjoy legally on Australian roads – but it is also supremely comfortable and well appointed. For Alpina fans lucky enough to be driven in on,e this would make for a truly rare and niche way to be chauffeured.

The S4 sedan and Avant have scored the bulk of design updates, with all new and recontoured side panels including the sedan’s C-pillar matching what was applied to the A4 earlier this year. 

This is paired with new front and rear facias and lighting for a subtle but extensive rework of the fifth-generation S4’s conservative look. 

The S5 Sportback, Coupe and Cabriolet get S5-specific new lighting and facias, but no sheetmetal changes. As before, the Coupe and Cabriolet ride on a 60mm shorter wheelbase than the Sportback, sedan and Avant.

The S5s also get Matrix LED headlights as standard which do a neat animated sequence when you unlock the car. 

Other visual hallmarks include new S4-specific 19-inch wheels, with S5 stepping up to its own unique 20-inch wheel. The six-piston front brake calipers are appropriately painted red, and there’s S-specific adaptive dampers under there too. All variants aside from the Cabriolet get a lip spoiler on the rear.

On the inside, there’s a new centre console and bigger 10.1-inch multimedia screen, while the Audi Virtual Cockpit driver instrument display now offers a hockey stick-style rev counter in additional to traditional dial layouts.

This is a good place to start because the B7 looks just like the 750Li it's based on, until you see the first tell-tale signs that it's not one.

There's the front wing with Alpina lettering and the boot-top spoiler, the graphics, which run the length of the car, and the 20-spoke wheels with Alpina badging.

This is late '70s, early '80s styling at its best (and possibly worst), but these special cars can pull off the irony-free look because this is how Alpina BMWs have rolled since 1975, when the E21 320-based Alpina A1/3 was launched.

BMW badges have been left on the bonnet and boot, but there's Alpina B7 BiTurbo lettering in place of the 7 Series identifier.

Most people walked by it in the street thinking it was just a big BMW, others scratched their heads wondering what I'd done to my big German limo and a handful almost dropped to their knees in praise and wonderment at spotting a rare beast like this in the wild.

These people all had their own Alpina stories – one was the third generation of an Alpina-owning family. You become a member a small and passionate club when you buy into this rarefied brand.

The standard B7's cabin is close to identical to the luxurious interior of the 750Li, save for Alpina-embossed stitching in the headrests of the soft, leather seats, the virtual instrument cluster and the Alpina plaque on the centre console denoting the build number.

The B7 is long, low and wide at just under 5.3m end to end, 1.5m tall and 1.9m across. A 3.2m wheelbase means cabin room is more than just spacious.

The B7 rolls off the Dingolfing production line in Germany and is then handed over to Alpina's facility in Buckle, where significant changes take place. Read on to find out how the B7 is different from a regular 750Li.

The biggest practicality change among the five S4 and S5 variants is their upgrade to the latest version of Audi’s MMI multimedia system, which steps up to a 10.1-inch touchscreen and drops the scroll wheel from the centre console.

It also boasts ten times the computing power of the version it replaces and uses this and an on-board sim card to access Google Earth maps for navigation and Audi Connect Plus that offers driver information such as fuel prices and parking information as well as point of interest search and weather information, plus the ability to make emergency calls and seek roadside assistance.

There’s also a wireless phone charger, but using Apple CarPlay will still require a cord as per Android Auto.

I only drove the S4 Avant and S5 Sportback at their media launch, which are clearly the most practical of the five, but from our experience with the previous versions, each looks after its occupants well in terms of space and storage. Back seat accommodation is clearly not a priority in the Coupe and Cabriolet, but there’s three other variants if that’s what you’re looking for. 

The Cabriolet can open its automatic folding soft top within 15 seconds, at speeds of up to 50 km/h.

The B7 is a five-seater limousine although with the fold-down rear centre armrest which houses the media control panel the back is really set up to carry two.

That 3.2m wheelbase means cabin space is enormous. At 191cm tall I can sit behind my driving position with about 30cm between my knees and the seatback. Those rear doors open wide and the entrance is huge, making entry and exit almost as easy as just walking through a doorway. The air suspension also rises and lowers the B7's ride height for better access.

Storage is excellent, with two cupholders and door pockets for rear passengers, along with the area inside the centre armrest.

Up front, the driver and co-pilot have a deep centre console storage bin with split-opening lid, two cupholders and door pockets.

Luggage space is good, with a 515-litre boot.

The B7 lists for $389,955, while a 750li is about $319,000. At this level, $70K seems like a downright reasonable premium to pay for a faster, more powerful, better handling and comfier version of the 750Li.

In this case you're paying more but getting more, although standard features are close to identical. There's adaptive LED headlights, head-up display, night vision with pedestrian detection, a 10.25-inch touch screen up front and two screens in the second row for TV and other media functions.

There's a reversing camera, sat nav, harman/kardon surround stereo and Apple CarPlay. There's leather upholstery, seat massagers in the front and rear, four-zone climate control, heated and ventilated front and rear seats, front and rear parking sensors, auto tailgate, sunblinds for the rear and rear-side windows and proximity key.

The safety features are listed in the section below, and that list is also impressive.

Rivals to the B7 include the Mercedes-AMG S63, which lists for $375,000, the $331,700 Audi S8 and even the Bentley Flying Spur, which almost matches its price at $389,500.

Audi has taken an ‘if it ain’t broke’ approach with the mechanicals, with all S4 and S5 models unchanged with this update. So the centrepiece continues to be the single-turbocharged 3.0-litre V6 that produces 260kW and 500Nm, with the latter available from a broad 1370-4500rpm.

The rest of the drivetrain is also unchanged, with the venerable but excellent ZF eight-speed torque converter auto paired with the Quattro all-wheel drive system that can send up to 85 per cent of drive to the rear wheels. 

Alpina takes the 4.4-litre twin turbo V8 from the BMW 750Li and rebuilds the engine by hand. Alpina fits its own turbochargers, air-intake set -up, high-capacity cooling system and Akrapovic quad exhaust. Output is 447kW and 800Nm – an increase of a whopping 117kW and 150Nm over the 750Li's grunt.

It's interesting to note that the V12-powered 760Li has a smidge more power, at 448kW, and the same torque output as the B7.

How fast is the B7? Supercar fast – the B7 has a top speed of 330km/h, which will see it outrun a McLaren 570 and almost keep up with a Ferrari F12. That's quite incredible for a 2.3-tonne limousine with three TVs on board. A 0-100km/h time of 4.2 seconds is also hugely impressive.

In comparison, a 750Li has a 0-100km/h time of a not-too-shabby 4.7 seconds, but the car is electronically limited to 250km/h.

An eight-speed automatic transmission shifts gears smoothly, although a little slowly in Normal mode, while Sport and Sport+ add urgency and harder shifts.

Finally, the B7 is all-wheel drive, and those rear wheels are designed to steer slightly for better cornering performance.

Official combined fuel figures range from 8.6L1/00km for the S4 sedan to 8.8L/100km for the Avant, Coupe and Sportback, while the heavier Cabriolet steps up to 9.1L/100km. 

All are pretty good considering their performance potential and the size of these cars, plus the fact that they only require 95 RON Premium Unleaded fuel.

All have a 58-litre fuel tank, which should enable a range of at least 637km between fills based on the Cabriolet’s figure.

The B7 is probably not the car to own if you're concerned about either fuel prices or emissions, but then the twin-turbo V8 may not be as thirsty as you'd think, with Alpina stating that, after a combination of urban and open-road driving, you should only use 9.6L/100km.

My time in the B7 saw me double that usage but this could have had something to do with me turning off the stop-start system and driving in Sport mode constantly.

The S4 and S5 range were already an excellent balance between everyday comfort and a genuine sporting edge, and nothing has changed with this update.

I spent time behind the wheel of the S4 Avant and S5 Sportback at their media launch, and both managed to deliver the proper Audi luxury experience over some pretty rough rural roads, while always feeling a bit more sporting than a regular A4 or A5. That’s with the Drive Select left in the default mode, but you can shift that sporting personality up a few notches (while scaling back the comfort), by selecting Dynamic mode. 

My preferred means of adjusting their personality is by simply tugging the transmission selector back to activate S mode, which livens up the engine and transmission without stiffening up the suspension. 

Across the five S4 and S5 bodystyles, there is some variance in performance potential, with the S4 sedan and S5 Coupe topping the performance chart with 0-100km/h boasts of 4.7s, with the S5 Sportback trailing them by 0.1s, the S4 Avant by a further 0.1s and the Cabriolet managing a still-fast 5.1s claim.

Another area I consider the S4 and S5s to get just right is their exhaust note. It is adaptive, but there’s nothing synthetic about it, and the generally muted and distinctly V6 burble is always there to remind you that you’re aboard a proper performance model, but not in such a way that it will annoy you, or your neighbours. Polite performance, if you will.

Who on Earth thinks a BMW 750Li isn't fast enough or comfortable enough, even with all its horsepower, luxurious cabin and technology? Alpina, that's who.

Redevelopment of the 4.4-litre V8 with new turbochargers, a high-capacity cooling system, different air suspension set-up and an exhaust system made by Akrapovic have made this already exceptional car better. Better to drive and better to be driven in.

The ride, even on those 21-inch wheels and low-profile Michelin Pilot Super Sport tyres (255/35 ZR21 on the front and 295/30 ZR 21 on the rear) is incredibly comfortable. I drove it and also had a chance to recline in the back and be chauffeured (by our photographer) and the ride was so composed and refined it was hard to believe I was travelling along some truly awful urban roads with their cracked and pot-holed surfaces.

And it's quiet, too. Which will suit those in the back being transported swiftly from the airport to their next meeting, but if you're after a loud and angry exhaust note then you won't find it in the B7. Sure, from the outside at full throttle the B7 has a menacing growl, but this isn't a BMW M car that will bark and snarl. 
See, while BMW's M division makes brutal, loud, high-performance versions of their regular cars, Alpina makes comfortable, stealthy, high-performance ones.

All-wheel drive provides fantastic traction and ensures that grunt doesn't just tear the tyres off those rims when you sneeze on the throttle.

And while the air-suspension is soft and comfortable, adaptive dampers adjust for when the road goes twisty, providing impressive handling for a heavy and long car.

Really, though, the B7 is built for long, endless stretches of roads, and the acceleration beyond 100km/h is almost as startling as that from 0-100km/h, as it wants to push straight past 200km/h towards that 330km/h top speed.

Which, unless you know a good lawyer or happen to be one, will send you straight to jail. Yes, the B7 is probably too much car for Australian roads. Only on a German autobahn would a B7 be fully at home.

I felt like I was given a Melbourne Cup-winning racehorse for a week but could only ride it in my suburban backyard.

The Alpina B7 comes with all of the BMW 750Li's safety equipment – this includes AEB, lane-keeping assistance and lane-departure warning, blind-spot warning, active cruise control, night vision with object recognition, auto parking and surround view camera.

Along with the suite of airbags, there's traction and stability control and ABS, as you'd expect.

The 750Li and B7 have not been given an ANCAP score.

Audi continues to offer a three year, unlimited kilometre warranty, which is in line with BMW but lags behind the five years offered by Mercedes-Benz these days. This also contrasts with the five year norm among mainstream brands, which is punctuated by the seven year warranties of Kia and SsangYong.  

Service intervals are a convenient 12 months/15,000km though, and the same five year ‘Audi Genuine Care Service Plan’ offers capped price servicing for the same $2950 total over five years applies to all S4 and S5 variants. This is only marginally more than the plans offered for regular petrol A4 and A5 variants, so you’re not being stung for the thoroughbred versions.

The B7 is covered by BMW's three-year, unlimited-kilometre warranty. Servicing is recommended every 12 months or 15,000km. The B7 is covered by BMW special vehicles servicing plan, which means services are cost-free for the first three years of the car's life.