When you line up the number of tuning firms who specialize on BMWs, you’ll inevitably come across Alpina, which technically started as an aftermarket company before turning into a manufacturer of its own after years of close ties with BMW. In fact,Alpina and BMW have become partners of sorts since most of the former’s models are integrated into the latter’s production lines, including the Alpina B7, which rolls from the same facility as the BMW 7 Series. That’s how far this relationship has come, and the German Ministry of Transport even recognizes it as such, designating Alpina as an automaker instead of an aftermarket specialist.
History lesson aside, Alpina is headed to the 2017 Geneva Motor Show with a number of its latest creations, one of which is the B4 S Biturbo, an interpretation of the 4 Series according to the specifications of Alpina. Like most models to come out of Alpina, the B4 S Biturbo is technically a 4 Series, and the process by which Alpina uses to create the car isn’t too different from what expert BMW tuners like AC Schnitzer do. So while it is technically an automaker, Alpina’s methods are still closer to AC Schnitzer than it is to BMW, hence the approach we’ve taken here.
The car itself is what you’d come to expect from Alpina. Like the B7 before it, the B4 S Biturbo is loaded with upgrades on all sections of the car, right down to the aerodynamic body kit and the engine upgrade that puts the B4 S Turbo’s power right up there with the BMW M4.
All told, the B4 S Biturbo is a car that’s worth our attention, not only because it’s an Alpina-badged model that’s based on the BMW 4 Series, but more importantly, because it checks off a lot of boxes on what we’d like to see the aftermarket world do to the 4 Series in the first place.
It may not be evident at first glance, but the Alpina B4 S Biturbo received a heavy dose of cosmetic and aerodynamic upgrades. On the aesthetic front, the German tuner is making its project car available in two distinct colors – Blue Metallic and Green Metallic – that it had a hand in personally creating, hence the “exclusive” label attached to each of the two colors. If customers aren’t too keen on either color, there is an option to instead get paint finishes from either BMW itself or the company’s personalization division, BMW Individual.
Since this is Alpina we’re talking about here, you can also expect the tuner’s recognizable decorative stripes included in the package. Alas, we see the stripes in all their glory running down the length of the B4 S Biturbo’s body. The tuner does offer an option to add the stripes in the front of the car in a choice between silver and gold colors.
The Alpina B4 S Biturbo received a heavy dose of cosmetic and aerodynamic upgrades.
Okay, now let’s move on to the aerodynamic enhancements, which may be limited in quantity, but still significant enough to affect the overall quality of the car. Up front, there’s a new front spoiler with an Alpina logo right smack in the middle of it, and at the back, there’s a new rear spoiler. Together, the two components not only create a more aggressive-looking 4 Series, but more importantly, they help enhance the coupe’s overall aerodynamic qualities. Rest assured, if a prospective customer wants to maximize the work Alpina put into the 4 Series, these aero bits will go a long way in addressing that.
The last piece of business as far as this section is concerned is the new set of 19- or 20-inch wheels. Customers can choose between the two sizes, both dressed in Alpina’s classic multi-spoke look.
What other tuners are offering
It’s hard to rival what Alpina has to offer, but fortunately, there are other tuners in the game that offer aerodynamic programs of their own. JMS, for example, has a front lip spoiler and integrated central diffuser on its menu.
Then, of course, there’s AC Schnitzer, which counts as one of Alpina’s peers in the BMW tuning scene. No surprise then that the German tuner’s upgrades include a new front spoiler and a new rear diffuser that provide improved ground adhesion for the German coupe. Carbon mirror covers, a rear skirt protective film, and a chromed front grille for 4 Series Gran Coupe M-Technik models are also available to anybody willing to get them.
Note: Side-by-side photo of the BMW 4 Series by JMS and the BMW 4 Series Gran Coupe by AC Schnitzer
What BMW is offering
It’s hard to go around these days looking for cosmetic and aerodynamic upgrades for a car like the BMW 4 Series without at least considering what BMW has to offer, be it with the company’s myriad of packages or options available for the sports coupe.
As far as the packages are concerned, there is a handful to choose from. For instance, there’s the Sport Line package, which adds high-gloss B-pillars, a black, wrap-around window strip, molded, high-gloss black grille slats, a chrome grille surround, black air intakes on the front apron, black air breathers, a black trim strip on the rear apron; and black exhaust tips.
Not digging all that black on the 4 Series? How does the M Performance Parts for the 4 Series sound? This option comes with an aero kit made up of a new front bumper with a carbon fiber splitter and larger air ducts, new front and rear carbon fiber spoilers, new side sills, and a boot deck spoiler that also happens to be made from carbon fiber.
Note: photo of the BMW 4 Series Coupe M Performance Parts
Befitting its status as one of the best BMW tuners in the business, Alpina spared no expense in giving the B4 S Biturbo a swanky interior upgrade. The tuner apparently prides itself on offering no limits on the possibilities of design and configuration of a car’s interior and it’s evident with all the luxury pieces and posh trims available for the 4 Series. First up is the interior trim, which Alpina is offering in either traditional fine wood or modern piano lacquer. There’s also the option to cover the interior trim in either sporty carbon leather or Lavalina, a bespoke material that’s exclusive to the master craftsmen over at Alpina.
Small details to the interior are also traditional Alpina additions to a lot of its projects. In the case of the B4 S Biturbo, the tuner added items like door sills, metal emblems in the seat backrests and in the floor mats, and since the car is of a limited edition variety, exclusive production plaques with each model having a specific build number. Those additions come on top of other additions like the tuner’s classic diagonal rhomb applications in the seat backrests, embossings, and other decorative elements.
Completing the interior upgrades is a new hand-finished sports steering wheel that can also be covered in Lavalina leather with contrast stitching in blue and green. Even better, customers can personalize the steering wheel of their car depending on their personal tastes.
What other tuners are offering
I think it’s safe to say that Alpina’s interior work on the 4 Series is as extensive as it’s going to get for the sports coupe. It’s not that other tuners like AC Schnitzer don’t have anything to contribute; it’s just that apart from the usual minor knick knacks like aluminum pedals, floor mats, and brake handles, the options are pretty slim pickings. There are some exceptions like Hamann, which provides its own extensive menu of interior upgrades. Just remember the words “premium leather,” “Alcantara,” and “carbon fiber;” there’s a pretty good chance that Hamann has those bits and pieces available for the 4 Series.
Note: photo of the interior of the BMW 4 Series by AC Schnitzer
What BMW is offering
It’s safe to say that BMW’s interior upgrade options are better than most of what customers are likely to get in the aftermarket tuning scene. Take the aforementioned Sport Line package for example. Not only does it come with an Anthracite headliner and Coral Red interior with leather sport seats, it also includes red-trimmed instrument dials and a red-stitched steering wheel.
Likewise, the M Performance Parts package is another option worth considering, just as it is on the exterior of the 4 Series. Those elements detailed above are complemented by interior upgrades made up of an Alcantara-wrapped dashboard and steering wheel, carbon fiber trim on the gear shift and hand brake levers, and stainless steel pedal covers and footrest, as well as M Performance floor mats.
Last but not least is BMW Individual, which as many of you already now, literally has a shopper’s list of exclusive upgrades. Where else would you be able to get seats, dash, and door panels wrapped in something like an Opal White, fine-grain Merino leather? That’s just a small sample of what customers can choose from as far as BMW Individual is concerned.
Note: photo of the interior of the BMW 4 Series Individual
Ah, yes. This section is the crowning glory of the Alpina B4 S Biturbo. Future customers should be happy to know too that Alpina’s past works on BMW models have yielded nothing but impressive results and there’s reason to be excited that this program won’t disappoint in that regard.
A pair of Alpina’s own turbochargers and a new high-performance cooling system count as the biggest additions to the 4 Series’ 3.0-liter straight-six engine. Those biturbos, in particular, are a piece of work given their ability to further improve the engine’s throttle response and generate top-end power, all while keeping its fuel efficiency numbers where they’re supposed to be, ultimately allowing the engine to maximize all of the available power at its disposal.
It certainly helps that the engine itself is configured with a specially cast aluminum crankcase with reinforced bed plate and Bi-Turbo capable flanges that allows Alpina to mount the biturbos for use with the engine without having to do too much work in reconfiguring the entire layout under the car’s hood. That’s important to remember since the tuner is also adding air intake ducts to help channel to air to the turbocharger without adversely effecting the amount of it that passes through.
Combine the newly added turbos with a high-capacity intercooler and cooling system, and you get a 4 Series that sees its output rise to 440 horsepower and 487 pound-feet of torque. Those figures represent an increase of over 100 horsepower and over 150 pound-feet of torque over the standard output of the 440i Coupe. Combine the power gains with an eight speed-sport automatic transmission and the B4 S Biturbo can sprint from 0 to 62 mph in just 3.9 seconds with all-wheel drive before peaking at a top speed of 188 mph. Rear-wheel drive versions are a little slower to 62 mph at 4.2 seconds but it does nip the AWD’s top speed mark with its top speed of 190 mph.
What other tuners are offering
Plenty of tuners have worked on the BMW 4 Series since the car first burst onto the scene back in 2013. There’s Hamannwith its plethora of software engine upgrades for variants of the 4 Series, topped by an upgrade on the 435i that brings the output to 348 horsepower and 331 pound-feet of torque, a nice increase from the variant’s stock output of 306 horses and 295 pound-feet of twist. AC Schnitzer also has a similar sofware program for the same 435i variant with the car’s power numbers slightly eclipsing that of Hamann’s program at 360 ponies. Another software program for the 435i comes by way of Best-Tuning, which was able to get the output of the straight-six engine to 365 horsepower.
Needless to say, Alpina’s B4 S Biturbo trumps a lot of what other tuners are offering. I mean, 440 horsepower and 487 pound-feet of torque is incredibly impressive given that those numbers are more than what BMW was able to get out the M4.
Check out the table below to see how the Alpina B4 S Biturbo stacks up against past programs for the BMW 4 Series.
|Model / Tuner||Horsepower||Torque||0 to 60 MPH||Top Speed|
|Alpina B4 S Biturbo||440 horsepower||487 pound-feet||3.9 seconds||188 mph|
|BMW 4 Series (435i) by Hamann||348 horsepower||331 pound-feet||4.8 seconds*||155 mph*|
|BMW 4 Series (435i) by AC Schintzer||360 horsepower||340 pound-feet*||4.7 seconds*||155 mph*|
|BMW 4 Series (435i) by Best-Tuning||365 horsepower||350 pound-feet*||4.6 seconds*||155 mph*|
Just to give you a scope of the extent of Alpina’s work on the 4 Series, the German tuner also put in its own sports suspension system on the sports coupe. It’s one that combines electronically adjustable dampers with springs, auxiliary springs, and anti-roll bars to help keep the coupe’s driving dynamics up to the standards set by the tuner.
The adaptive Alpina sports suspension combines electronically adjustable dampers with springs, auxiliary springs, and anti-roll bars. Independent of the active dampers continuously adapting to the current driving conditions, the driver can also noticeably adjust the suspension and overall driving dynamics towards a more comfort or sport orientated setup. The program also features a Dynamic Performance Control button that can be used to select different modes of the electronically adjustable dampers that function in a way that influences how the B4 S Biturbo is driven. These enhanced features should be a boon to future owners of the Alpina-tuned 4 Series.
Speaking of enhancements, let’s not forget the limited-slip differential since it’s arguably one of the most important features of the B4 S Biturbo. Not only does it help improve the coupe’s traction, but it also helps improve the overall handling and drivability of the car, especially when it’s put through the paces in a racing environment.
Prepare to shell out a significant sum of dough for the Alpina B4 S BiTurbo as pricing for the model starts at €63,277 for the standard rear-wheel drive model, or just under $67,000 based on current exchange rates. Meanwhile, the xDrive all-wheel drive variant sells for €65,714, or about $69,600. Both models are equipped with an eight-speed, sport-automatic transmission with Alpina’s Switch-Tronic technology.
Prepare to shell out a significant sum of dough for the Alpina B4 S BiTurbo as pricing for the model starts at €63,277 for the standard rear-wheel drive model, or just under $67,000 based on current exchange rates. The xDrive all-wheel drive variant sells for €65,714, or about $69,600. Both models are equipped with an eight-speed sport-automatic transmission with Alpina’s Switch-Tronic technology. Considering that the BMW 440i comes with a starting price of just under $50,000, paying for that extra $20,000-something counts as a good deal to us.
BMW 4 Series Gran Coupe By AC Schnitzer
AC Schnitzer makes a second appearance here for its separate program for the Gran Coupe version of the BMW 4 Series. Similar to what we can expect from the tuner, this program is made up of a variety of upgrades to the engine’s control unit and the intercooler. Take the 428i, which in standard form is capable of producing 240 horsepower, but with AC Schnitzer’s aftermarket wizardry, that output goes up to 294 horsepower.
Other trim models like the 420i also received significant power bumps from 184 horsepower to 245 horsepower while the diesel variants like the 420d, the 430d, and the 435d received their power bumps amounting to 218 horsepower, 309 horsepower, and 360 horsepower, respectively. Last but not least is the 435i and its 3.0-liter inline-six engine, which sees its output increase from 300 horsepower to 360 horsepower.
Alpina’s reputation is as rock solid as any tuner that’s out there and even saying that feels like an understatement. The truth is that the German tuner is good at what it does, especially when it comes to BMW models. That’s a big reason why the B4 S Biturbo is as well-prepared a program as we’ve seen for the BMW 4 Series. It covers a lot of ground without stepping outside the lines, thus creating an ideal marriage of exterior, interior, drivetrain, and suspension upgrades that combine to create an impressive interpretation of the 4 Series.
- Plenty of bespoke materials
- Engine upgrades are impressive
- Improved riding and handling credentials
- Hard to come by
- Lots of competition
- Could’ve had more power