Mercedes-Benz GT vs BMW Alpina B4

What's the difference?

The Mercedes-AMG GT Black Series is a rare beast; in the sense that it’s both unattainable and that it makes you feel like a superhero behind the wheel.

There is more performance on offer than most can hope of using, but the best thing about Mercedes’ latest supercar is its approachability.

In my experience, the more expensive a car gets, the more stressful driving them becomes, but the Mercedes-AMG GT Black Series does something I didn’t think was possible, and turns a near-$1 million supercar into something fun.

You could almost call the B4 S the anti-M4. It's still fast and practical but from a completely different perspective. It's much more a grand tourer than the M4 and even with the Akrapovic exhaust (usually a byword for joyous, anti-social racket), subtle.

For some, the price won't matter because the Alpina delivers what they want - M4-like straight line performance without the histrionics or the uncompromising chassis. And there's also a bit of that perverse exclusivity of the styling that you won't get anywhere else.

Most high-performance brands have their hardcore, track-focused models, from the Porsche 911 GT2 RS to the McLaren 765LT and the Ferrari 488 Pista.

For Mercedes-Benz, it’s the Black Series, a badge which could be found in the past on the SLK, CLK, SL-Class, C-Class, but for 2021 it’s now found on the back of the GT supercar.

To differentiate it from the rest of the ‘standard’ Mercedes-AMG GT range, a slew of racecar-like components are added, such as a fixed rear wing (with deployable insert), vented front fenders, extended front splitter and fixed-back seats.

In fact, so different is the Black Series, that the only panel that carries over from the GT is the roof, which is a carbon-fibre component to keep weight down.

Other carbon-fibre bits include the front fenders, front and rear bumpers, and rear hatch.

The most in-your-face addition might be the deeply vented bonnet, designed to evacuate hot air from the engine bay, while the hero 'Magma Beam' orange colour that juxtaposes all the exposed carbon-fibre panels is a real attention grabber.

From the outside, the Mercedes-AMG GT Black Series is bold, brash and in-your-face, but that’s exactly what a race car should be – in my opinion, at least.

I absolutely love how the Black Series looks like a Need for Speed or Forza Horizon video game car brought to life, and will turn heads anywhere you go.

Inside, the Black Series is clad in soft-touch 'Dinamica' and orange contrast stitching across many of the touchpoints such as dashboard, steering wheel and door cards.

And with fixed-back bucket seats, a racing harness and a roll cage, you’d be forgiven for thinking the AMG GT Black Series is all about function over form, but there are small touches to make it easier to live with on the road.

The multimedia touchpad controller falls easily in hand, while the shifter is flanked by an array of light-up buttons to adjust settings like adaptive suspension, exhaust note and rear spoiler angle.

Overall, the Black Series’ cabin is well-laid out like a standard AMG GT, with some nice flourishes to stand it apart.

Alpina has always had a particular aesthetic that could uncharitably be termed as mid-'80s West German - all set square angles and body graphics. Think David Hasselhoff's Berlin Wall look. The company has never really deviated from adding squared-off body bits to the various BMWs it has rebadged under its long-running agreement.

For the B4S, Alpina adds the signature billion-spoke alloy wheels (only a slight exaggeration), a new front splitter complete with Alpina lettering, a weirdly proportioned boot lid lip spoiler and - not even joking - pinstripes. Like I said, mid-'80s West German. You can still recognise the sleek 4 Series Coupe but perhaps the worst of it is the super-sized, wonky-looking ALPINA B4S on the boot.

Inside is rather more restrained apart from the ill-fitting Alpina plaque under the climate control. Again, it's all 4 Series in here, with the lovely Merino leather liberally applied across the cabin. Less lovely is the wood on the door pulls and console but the door cards have an oddly appealing woven leather which looks and feels good.

Sadly the standard 4 Series steering wheel is along for the ride. There's nothing wrong with it - although the Alpina logo does look out of place - but if I were a product planner, I'd beg for the lovelier M wheel.

As a two-seat coupe, the AMG GT Black Series isn’t the most practical of cars, but then again, it isn’t trying to be.

The cabin is big enough to accommodate six-foot tall (183cm) passengers like myself, though the fixed-back seats are designed to be form-fitting even for slender frames.

Storage options inside include two cupholders and a shallow underarm storage cubby, and that’s about it.

Unlike the standard GT, the Black Series’ doors forgo the small storage pocket – likely to keep weight down.

Opening the boot reveals enough space for a set of golf clubs or a few weekend bags, but not much else.

Mercedes does not list the volume available in the Black Series, but with the inclusion of a rollcage and special reinforcement components to help transfer the downforce of the rear wing to the chassis, it’s safe to assume it is less than the 176 litres offered in the AMG GT.

If you're in the front, you're in luck - it's a comfortable place to be, with plenty of leg and headroom. Down back isn't terrible despite the coupe roofline. The two seats are nicely shaped for maximum comfort and separated by an odd plastic tray. The fold-down armrest has two cupholders.

Front seat passengers score a pair of cupholders (bring the total to four for the car) and the long doors will hold a bottle each.

The boot swallows a reasonable 445 litres, which isn't at all bad.

If you thought BMW don't mess about when pricing up its cars, you best strap yourself in. The 440i-based B4S starts at a solid $149,900. That's $48,000 more than the 440i and significantly more than an M4 Pure. But there's plenty of gear on offer and some genuine, bespoke Alpina additions.

Standard are 20-inch signature Alpina alloys, 16-speaker harmon kardon-branded stereo with DAB, super-soft Merino leather everywhere, dual-zone climate control, around-view cameras, reversing camera, sat nav, keyless entry and start, front and rear parking sensors, active cruise control, heated and electric front seats, head-up display, auto headlights and active LED headlights, LED taillights and electric sunroof.

The stereo and sat nav are run by BMW's iDrive. It's a cracker of a system and almost gets away without Apple CarPlay and Android Auto. The absence of such simple pleasures at this price point is a bit lame, but here we are.

Powering the GT Black Series is AMG’s ubiquitous 4.0-litre twin-turbo-petrol V8 engine, with a few modifications.

For starters, a flat-plane crank is used for the V8 for improved throttle response, less weight and different firing order that makes it more free revving than the standard engine.

In fact, so different is the engine that Mercedes-AMG has given the Black Series’ powerplant its own internal code, with only three technicians in Affalterbach qualified to put it together.

The result is peak power of 537kW available from 6700-6900rpm, while maximum torque reaches 800Nm, on tap from 2000-6000rpm.

For those keeping track, that’s 107kW/100Nm more than the GT R.

Sending drive exclusively to the rear wheels via a seven-speed dual-clutch automatic transmission, the AMG GT Black Series will accelerate from 0-100km/h in just 3.2 seconds and top out at 325km/h.

A lot of your extra money turns up under the bonnet. These days the 440i packs BMW's slick B58 turbo straight six and the B4S does likewise. The boys from Buchloe in Bavaria (there are certain to be women there, too, I just liked the alliteration) added a pair of Alpina-spec turbos to generate a whopping 324kW and, more importantly, 660Nm. Alpina says 600Nm (the max torque figure of the brilliant M4 CS) is available from 2000-5000rpm, while the full 660Nm is available from 3000 to 4500rpm.

The M4 Pure has 317kW and 550Nm from the S55 straight-six. Just so you know.

Like the 440i but unlike the M4, the B4S employs the dependably brilliant eight-speed ZF automatic found throughout the BMW range.

Officially, the GT Black Series will consume 13.2 litres per 100km, making it thirstier than the GT R that returns 11.4L/100km.

The GT Black Series will require 98RON petrol and this, coupled with the high consumption average, will mean a big bill at the bowser.

However, as such a focused performance machine, fuel economy in the Mercedes-AMG GT Black Series is less of an important point than something like a charismatic and dynamic engine.

Alpina quotes 7.9L/100km on the combined cycle and we went through the premium unleaded at the rate of 11.7L/100km. I enjoyed myself, so that's not a terrible result.

We’ve driven some very fast cars before, so make no mistake when we say the AMG GT Black Series is seriously quick.

The right pedal might as well be warp drive on the, Starship Enterprise, because as soon as you floor the throttle, you’re pinned to the back of the race seat and the only reprise comes from lifting off.

Aside from the immense speed, what is – surprisingly – noticeable is the noise, or lack of it.

The flat-plane crank V8’s different firing order means it doesn’t have the same burbly notes as the standard AMG GT, it’s a racier tone. That’s not a bad thing, mind you, just a different note.

And while the flat-plane crank V8 changes the exhaust note, it also makes the engine freer revving and lively.

With 537kW/800Nm on tap, you sort of have to trust the suspension and aerodynamics will do their thing to keep the AMG GT Black Series on the track, and it’s here where I think Mercedes-AMG has pulled off some sort of magic.

The combination of adaptive dampers, active aero, beefed-up anti-roll bars and a unique Michelin Pilotsport Cup 2 R tyre (featuring a silhouette of the Black Series laser etched into the sidewall) results in a terrifyingly capable vehicle at Phillip Island.

I am the first to admit that I am no Lewis Hamilton behind the wheel, I often get on the throttle too early, I can never nail a double-apex corner and my heel-toe-technique could use more work, but behind the wheel of the GT Black Series, I felt like Ayrton Senna’s spirit had taken the wheel on my behalf.

Cornering in the Black Series felt like nothing else, and regardless of what the speedo was saying, the nose of the ferocious GT flagship would just point wherever I wanted it to go.

Luckily the braking system is also up to task – thanks to carbon ceramic units fitted as standard, as well as unique pads and discs.

The brakes bite almost immediately, giving you the confidence to hit the stop pedal at the last moment before tipping into a corner.

I think the biggest compliment I can pay to the Mercedes-AMG GT Black Series is that it increases that narrow band of fun you can have in a supercar.

Sure, a driver with more skill could pilot the AMG GT Black Series with more grace, and finesse it around the corners a little quicker, but the approachability of the performance on offer is amazing.

Nothing feels intimidating, nothing feels unapproachable. The GT Black Series is so communicative that it gives drivers the confidence to feel like a hero around a race track.

If there is any criticism of the car, it’s that its limits are so high they are hard to explore, even on a circuit like Phillip Island, but maybe that takes more skill than I have, or more than just a handful of laps behind the wheel.

Of particular note, too, is that the engine of the Mercedes-AMG GT Black Series is found in the front.

There’s a reason why some exotic supercars will opt for the mid- or rear-engine layout, but Mercedes has managed to craft a front-engine, rear-drive machine that will keep up with the best the world has to offer.

One of the key differences between the B4 and M4 is the ride. While the M4 can crash over bumps and generally be a little hard to live with, the crew in Buchloe have gone after a much more plush ride. And in that they have succeeded because the B4 S is a mighty fine cruiser. Bumps are dismissed with a haughty disdain, even Sport + silliness doesn't completely write-off ride quality.

Very impressive too, is the steering. While still not at Lotus Elise levels of feel (few cars are), the Alpina tweaks connect the your palms to the road with more clarity than what you'll find in the 440i or M4. Where the M4 particularly adds too much weight, the 440i is a bit more circumspect in that regard.

And then we come to the engine. The B58 six is a belter, better even than the N55 that preceded it. It's still a 3.0-litre straight six but is part of BMW's modular engine family that starts with a 1.5-litre triple in the Mini and 1 Series. The Alpina-spec turbos are noisier, the Akrapovic exhaust lighter and also noisier. It doesn't have the all-out crackle and pop of an Audi or Merc (perish the thought), but when you're on it, the B4 means business. The 660Nm of torque, available over a wide rev range, delivers a steel fist wrapped in a velvet glove and bubble wrap - the speed builds rapidly but smoothly. 

The approach to the chassis tune seems to be based on the driving talents of mere mortals on normal roads, which is kind of like the 440i. It's terrific fun to drive hard but it's very forgiving and patient. The great thing about it is that you wouldn't think twice about jumping in it for the long haul, so comfortable and quiet is the cabin. The M4 will leave it for dead on a winding road, but that's perfectly fine.

One irritant is the replacement of the admittedly cheap BMW gearshift paddles with weirdly non-tactile buttons. They're not particularly easy to use and, probably worse for a sporty car, unsatisfying. It's an odd detail with which to go off the reservation. Cheeringly, the eight-speed ZF is its usual perfect self, so you don't have to worry too much about manual mode or go old school and use the shifter.

The Alpina ships with six airbags, ABS, stability and traction controls, ABS, stability and traction controls, forward collision warning, forward AEB, road sign recognition and active cruise control.

There are also two ISOFIX points in the rear. Neither the Alpina nor the 4 Series has an ANCAP safety rating.

Like all new Mercedes models sold in 2021, the Mercedes-AMG GT Black Series comes with a five-year/unlimited kilometre warranty with roadside assist over that period.

Mercedes’ warranty easily outclasses other premium marques like BMW, Porsche and Audi, who each offer a three-year/unlimited kilometre coverage, and Lexus (four year/100,000km), while matching Jaguar and newcomer Genesis.

Scheduled servicing intervals are every 12 months or 20,000km, whichever occurs first.

Servicing costs for the Black Series were unavailable to us at the time of publishing, but maintenance of the GT coupe will ring the till up at $4750 over three years.

Alpina offers a two-year/unlimited-kilometre warranty which is a bit behind the times and not in keeping with the price point. Servicing is another matter altogether and you're subject to your dealer's standard charges for servicing.