The current F90 generation M5 is an incredible machine capable of producing 600hp and takes an eye-watering 3.4 seconds to complete the 0-100kph sprint. Then, M5 Competition came along and turned up the performance with 617hp and an incredible century sprint of just 3.1 seconds. This, however, wasn’t enough for the boffins at BMW’s M division, and they continued tinkering away until they birthed the truly monstrous, and quite frankly ridiculous BMW M5 CS.

Following its smaller siblings, the M2 CS and M3 CS, the M5 CS is the ultimate incarnation of the BMW M5 and the first M5 to carry the ‘CS’ moniker. This badging, used sparingly and reserved only for the highest performing BMW’s, clearly indicates the intent and the performance potential that this new M5 will bring to bear.

A big part of the ‘CS’ treatment for the M5 is its weight reduction. The M Division has put the M5 on a diet, mainly focusing on the extensive use of carbon fibre on the exterior. Carrying over the carbon roof from the M5 Competition, the M5 CS employs a carbon fibre hood and carbon front splitter and side mirror shrouds taken from the M8 coupe. On top of that, the carbon boot-lid spoiler and very large (and very functional) rear diffuser provide a bulk of the near 70kg weight reduction over the M5 Competition.

While still distinctly an M5 in appearance, subtle hints set the M5 CS apart from other M5 variants. Gold bronze is the colour theme of the M5 CS, with this exclusive hue donning the kidney grilles surrounds and the M gills on the flanks. The M5 CS comes available in three different paint shades – Brands Hatch Grey metallic or two exclusive BMW Individual matte paint finishes; Frozen Deep Green metallic and Frozen Brands Hatch Grey metallic.

Among other tell-tale traits of the M5 CS are the unique forged, 20-inch Y-spoke designed wheels and the quartet of large stainless steel exhaust pipes that are also finished in the gold bronze colour. Even the L-shaped running lights emit a distinctive yellow tone found nowhere else on the BMW range. The cherry on the cake is the numerous ‘CS’ badging dotted around the car, making sure everyone knows this is no ordinary M5.

While the extensive use of carbon and the updated exterior add to the ‘CS’ package, the real moneymaker is in the go-faster bits. The M5 CS sports the most powerful M engine ever — a 4.4 litre twin-turbo V8 pumping out 635hp and a whopping 750Nm of torque. That’s 10hp more than the M5 Competition. Mated to an 8-speed M Steptronic transmission and powering all four wheels via BMW’s M xDrive all-wheel-drive system, the M5 CS completes the 0-100kph sprint in a mind-boggling three seconds flat. 0-200kph is achieved in just 10.4 seconds while top speed is electronically limited to “just” 304kph.

To manage this immense power, BMW has beefed up the chassis of the M5, building on the chassis of the M5 Competition. Uprated engine mounts better connect the engine to the chassis for improved stability during hard acceleration and cornering. Adding to the overall ride comfort and on-the-limit handling, the M5 CS borrows the M8 Gran Coupe’s shock absorbers, albeit with retuned damper control to account for the car’s lower weight.

The M5 CS’ 20-inch wheels come wrapped in ultra-aggressive Pirelli P Zero Corsa track tires, measuring 275/35 R20 at the front and 285/35 R20 at the rear, to ensure power isn’t wasted with spins. Behind those gorgeous gold-bronze wheels hide massive M Carbon ceramic brakes that deliver superb stopping power and are fitted as standard. The callipers are six-pistons at the front with a single-piston floating calliper setup at the rear that are finished in a striking red colour, or optionally in the gold bronze hue of the M5 CS. The carbon-ceramic brakes are 23kg’s lighter than the ones found in the M5 Competition, and offer even better braking performance for daily use as well as pounding them on the occasional track day.

While the hardware on the M5 CS is plenty impressive on its own, it’s the tech that governs how this big beast runs that is the ace up its sleeve. Controlled through the latest iteration of BMW’s iDrive, drivers can individually configure both the M xDrive system and all the driving dynamics components to tailor the handling characteristics to their preference. The rear-wheel biased setup of the M xDrive grants the M5 CS exceptional agility. Besides, the driver can vary the distribution of power between the front and rear wheels. For those who love to hoon about, the M5 CS can switch to purely rear-wheel drive mode, and DSC (Dynamic Stability Control) system can be adjusted to allow massive powerslides for days on end!

The Variable Damper Control (VDC) system offers the Comfort, Sport and Sport+ driving modes. As the name suggests, Comfort mode is meant for comfortable, daily driving. In contrast, Sport mode stiffens up the suspension for optimal body control and improved throttle response. Sport+ on the other hand, turn things up to eleven, unleashing the full beast mode of the M5 CS, maximising performance on the street and the track, with wheel and body movements kept at a minimum. The sports exhaust system will also be fully activated to let the might bellow of that V8 reverberate.

Sure the M5 CS is a performance monster, but on the inside, it’s still a luxurious 5 Series…somewhat. The most noticeable difference is that it’s a 4-seater, rather than the traditional 5-seat layout. The four individual M Carbon bucket-style seats exclusive to this special-edition, in keeping with its performance prowess. The electrically adjustable carbon seats are wrapped in Merino leather with red double-stitching, and come with illuminated M5 badging and the outline of the legendary Nürburgring circuit imprinted on the headrests.

Being a race-inspired interior, Alcantara is prominently used on the headliner and the M Sport steering wheel. The gearshift paddles are made from carbon fibre, and the steering wheel spokes have Black Chrome trim with two red-painted M1 and M2 buttons next to the gearshift paddles. Drivers can switch between the Road, Sport and Track settings using the M Mode button and the two individual setups with their choice of M xDrive, DSC, engine, transmission, damper and steering characteristics, as well as their desired M View configuration in the Head-Up Display.

The centre-piece of the interior is a massive 12.3-inch touchscreen display that shows the driver the myriad functions of the M5 CS, from drivetrain performance to media settings. M View in both the instrument cluster and the Head-Up Display is activated in Sports mode, displaying only relevant information for performance driving such as rev counter, shift lights, a digital speed readout and the current gear. Navigation instructions can also be configured to be displayed in this layout.

As part of the BMW Operating System 7, a whole host of digital services are made available in the M5 CS, including the latest extended BMW Intelligent Personal Assistant and Remote Software Upgrade functionality. Smartphone interfacing with Android Auto and Apple CarPlay is also part of the standard features.

The M5 CS is a serious performance machine designed to beat super-saloon and supercars while carrying four passengers. Despite its ferocious appearance and apocalyptical performance, it is still a comfortable, practical and liveable car.