Audi S4 vs BMW Alpina B5

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 Alpina B5 is a special car – more special than most people will ever give you credit for if you own one. Those that do know what an Alpina is will let you know; people will cross dangerously busy streets to talk to you about your car. Insanely fast, almost incomprehensibly comfortable and effortlessly powerful to drive.

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.

Interesting is the right word for it, because while it might be questionable that Alpina's changes to the exterior are aesthetic pleasing, they are definitely intriguing to those who aren't familiar with the brand.

First, there are those 20-spoke wheels. Alpinas have worn this style of wheel forever and they've become the most famous outward sign that this is not just another BMW. So don't under any circumstances take them off and replace them with anything else. You'd be run out of town by the Alpina mafia.

Yes, they're more painful to clean than a cheese grater (trust me, I know. And if you look closely at these images you can see the dirty bits I've missed), but if you really don't like them then perhaps it's a sign this car isn't for you.

Then there's the boot-lid spoiler. It's square and 1980s'-looking, it also appears a bit like it's been bought online and installed by a teenager, but again, this is another Alpina tradition and it suits the car's character perfectly.

All right, those pinstripes; they're known as the Deco-Set and are a hat-tip to the Alpina racecars of the 1970s and '80s. Again, don't take these off, your Alpina will drop through the centre of the Earth in value. These are also part-and-parcel of owning one of these cars. I'm not a massive fan of them.

But I'm all about that front spoiler, with the floating Alpina lettering that you can option in silver, high-gloss black or gold.

Inside, there are fewer Alpina additions, but they're nonetheless unmissable. There's the Alpina-badged steering wheel, and a new virtual instrument cluster, embossed headrests and  illuminated door sills.

There's also the little numbered plaque on the centre console which proves its authenticity, ours was number 49. Out of how many? I don't know. But I do know Alpina produces only about 1700 cars globally a year. Rolls Royce does about 4000. So, you can rest assured your B5 is exclusive.

At almost 5m long, 1.9m wide and 1.5m tall, the B5 is a large saloon, but having recently reviewed the Alpina B7 it feels small in comparison. How does it drive? We're getting there.

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.

Practicality is not really a BMW strong point no matter which model you pick. See, BMW mostly makes the car equivalent of uber-stylish and skin-tight active wear which looks good and performs brilliantly, but sometimes you just want pockets and a bit of room for your… um… bits and pieces.

So while there are two cup holders up front and two in the back, the bottle holders in the doors aren't huge, the centre console bin is on the small side, there's a hidy-hole in front of the shifter, the glove box is just a box for little more than gloves and there's no other great cabin storage options.

Legroom in the rear is good but not great, too - I'm 191cm tall and have about 30mm between my knees and the seat back in my driving position. Middle-seat passengers will also have to straddle the drive shaft hump in the floor. Headroom is restricted in the back, too (you could blame the sunroof) with my hair just skimming the headlining (I do have big hair).

Under that power tailgate, the B5's boot capacity is 530 litres which is 15L more than its big sister, the B7. There are two plastic storage areas either side of the luggage space for wet things. While there is one USB outlet in the front there aren't any in the rear.

The BMW Alpina B5 lists for $210,000, making it only $10K more the BMW M5 which comes with almost identical features apart from the Alpina engineering to the engine and chassis.

Arriving standard is leather upholstery, four-zone climate control, nav, the Alpina embossed-headrests, a 10.25-inch display, digital radio, Alpina door sills, sunroof, proximity key, power front seats, 12-speaker Harman Kardon stereo, head-up display, Alpina virtual instrument cluster, heated front and rear seats, and the 20-inch Alpina wheels.

The test car I drove had been optioned with a limited-slip differential ($5923), steering-wheel heating ($449); soft-close function for doors ($1150); sunblinds ($1059); TV function ($2065) ambient air package ($575), and front-seat ventilation ($1454).

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. 

The Alpina B5 uses the same 4.4-litre V8 engine found in the BMW M5 (and also the B7). But, and it's a big but, the M5 makes 441kW and 750Nm, while the B5 outdoes it with 447kW and 800Nm. Admittedly, the B5's torque arrives at the 3000rpm mark, while the M5's is all there from 1800rpm.

How does the B5 beat it? Alpina installed its specially developed twin turbochargers and intercoolers, a high-performance cooling system, a reconfigured air intake set up and a different exhaust system.

The B5, though, is a tenth of a second slower to 100km/h compared to the M5 with a time of 3.5 seconds, but it will blast on to a top speed of 330km/h while the M5 is limited to 250km/h in regular form and 305km/h with the optional M Driver's package.

Both uses the same ZF eight-speed automatic transmission with identical gear ratios, and both are all-wheel drive.

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 Alpina B5 needs petrol. By that, I mean it needs quite a lot of it if you want to enjoy it properly. What type of mileage does it get? Officially, it should use 11.1L/100km after a combination of urban and open roads, where as the M5 is set to 10.5L/100km.

That makes sense, the B5 produces more power and torque, and it's 85kg heavier than the M5 at 2015kg.

Our test car's trip computer was reporting 13.2L/100km after flying low over country roads and slow city piloting. The more time spent in the urban warfare that is the daily peak hour commute, the more that figure crept and hovered around the 15L/100km mark.

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.

Ok, stay with me here. For this next bit you'll need a fresh egg, a lounge chair, and it might be a good idea to have some plastic bags and carpet cleaner on hand.

First, in front of the lounge chair flatten out the plastic bag and place the egg on it. Next, sit down on the chair and very carefully rest the ball of your foot on the egg with as little pressure as humanly possible.

This is exactly how little force you need to apply to the go-pedal of the B5 to accelerate from a standstill to 60km/h in about five seconds.

If anything sums up the driving experience of the B5, it's that sense of effortlessness.

Stomp on that accelerator, and you'll be shot to 100km/h in 3.5 seconds, without a hint of broken traction thanks to the all-wheel-drive system.

The ride should have been terrible on 20-inch wheels shod in low-profile rubber (Pirelli P Zero 255/35 front, and 295/30 rear), but the Alpina-tuned air suspension is close to miraculous in the way it cushioned and censored the potholes out of Sydney's worst roads. Yes, it can be a touch floaty, particularly in the Comfort Plus setting, but this is benchmark-setting stuff for a comfortable ride.

Don't expect this beast to roar. Unlike the M5, the B5 gets its work done without deafening everybody around it. Sure, the B5's V8 sounds amazing when you push it, but it's not brash, not loud and not lairy. Buy an M5 or Mercedes-AMG E63s if you want to be heard half a block before you get home, but you won't get that with the B5 and its exhaust system.

The B5 also handles well, but I have to say the engagement factor is low. I piloted it effortlessly through the twists and turns of my country test circuit and roads which normally have me grinning like a maniac behind the wheel had me feeling a bit disconnected in the B5. That air suspension, the numb steering and pedal actions make it difficult to ‘feel' the road.

It's highways where the B5 is a king, but even at 110km/h there's the sense that this car is still fast asleep and won't get out of bed for anything less than 150km/h - making it perfect for Germany's autobahns, but maybe not for here in Australia.

The Alpina B5 is based on the BMW 5 Series which had a five-star ANCAP rating awarded to it in 2017.

Along with the comprehensive suite of airbags, traction and stability control, there's an impressive array of advanced safety equipment. Coming standard is AEB (front and rear), evasive steering, front and rear cross-traffic warning, blind-spot alert and lane-keep assist. The Alpina B5 also comes with BMW's emergency call function.

For child seats you'll find two ISOFIX mounts and three top tether points across the rear row.

safety

If you're unfortunate enough to get a flat tyre, there's a puncture repair kit in the boot which works provided the hole isn't giant, as I've experience in the past with these systems.

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 Alpina B5 is covered by BMW's three-year/unlimited kilometre warranty. Servicing is recommended every 12 months or 15,000km.