Review and road test of the BMW M5 CS
M C SQUARED
BMW's M5 CS aims to further redefine what a super saloon should be. Jonathan Crouch takes a look.
Ten Second Review of the BMW M5 CS
BMW's M5 CS is the most powerful BMW M car ever, with 635hp, a rest to sixty time of just 3.0s and a top speed of 189mph. You'd really need track day membership to justify ownership of this super saloon - and its huge price tag - but if you're brave enough to push this V8 powerhouse to its ultimate limit, you won't be disappointed.
It must have been quite a challenge for BMW to make their M5 Competition super saloon even more focused - but that's what we've got here with this car, the M5 CS. 'CS' originally stood on BMWs for either 'Club Sport' or 'Competition Sport' and the Bavarian marque has used this badge in recent years to identify various even faster versions of its full-M models - usually M3s and M4s. The result has tended to be machines really most suited to the track, but BMW assures us that this M5's remit as an uber-capable road car has been retained here.
It gets a smaller weight reduction - and an even smaller power hike - but a range of detail engineering changes will please enthusiasts, particularly those looking to take this car on track.
As we'll tell you later, this M5 CS costs significantly more than a standard M5 Competition, so what do you get that's different? Well, the most powerful engine that BMW makes for a start, this 4.4-litre V8 developing 635hp, so 62mph from rest takes 3.0s on the way to 189mph. Mind you, that's not much different to what you get with the standard M5 Competition (625hp, 62mph from rest in 3.3s and a limited top speed of 155mph). The Drivelogic-equipped M Steptronic 8-speed paddleshift auto transmission isn't much changed either.
But BMW says you need to drill down into the detail here. The CS features a seven-millimetre drop in ride height compared to the standard model, plus it's 70kgs lighter and gets shock absorbers developed for the BMW M8 Gran Coupe. These reduce fluctuation in wheel loads, greatly improving on-the-limit handling. The bearing springs at the front and rear axle of the M5 CS have been retuned and damper control has also been refined in keeping with the lower vehicle weight and the bespoke Pirelli P Zero Corsa tyres' increased performance potential. Plus the engine mounts get an upgraded spring rating, while the V8 itself gets optimised turbochargers and has maximum injection pressure of 350 bar for shorter injection times and improved atomisation of fuel.
As in a normal M5 Competition, you can tailor the M xDrive 4WD system to your preference - via '4WD' and '4WD Sport' - or a '2WD' mode for pure rear wheel drive and circuit drifting. And of course there's the usual 'M-configuration' that allows you to alter stability settings, engine response, suspension and steering feel, with red wheel-mounted M short-cut buttons.
Design and Build
A range of little details mark this M5 Cs apart from its M5 Competition stablemate. The bonnet is made entirely from lightweight CFRP (CarbonFibre Reinforced Plastic). The front splitter and the exterior mirror caps - taken from the BMW M8 - together with the additional rear spoiler on the boot lid and the rear diffuser are also made from CFRP. The M5 CS sports exhaust system's quartet of stainless-steel tailpipes and Gold Bronze accents will also be noticed by the Bavarian cognescenti. Who will also pick up that the kidney grille surround on this CS variant is finished in Gold Bronze, as are the M gills on the front wings and "M5 CS" badges on the kidney grille and boot lid. The 20-inch M forged Y-speed wheels get a Gold Bronze finish too.
Step inside and you'll find that the interior layout - comprising four individual M Carbon bucket-style seats - is exclusive to the CS model. The fine-grain Merino leather covers for the front seats and their Merino leather counterparts on the exclusive individual seats in the rear come in black with eye-catching contrasting panels and decorative stitching in Mugello Red. The outline of the legendary Nurburgring circuit imprinted on the head restraints is a reminder of the car's sporting potential. The rim of the M Alcantara steering wheel is wrapped in the race-derived material from which it takes its name, while its centre-marker perforation with red background is another classic race car influence. The gearshift paddles are made from carbon fibre and the steering wheel spokes have Black Chrome trim. Elsewhere, Alcantara is also used for the headliner. To save weight, a fixed lightweight cover sits atop the centre console (replacing the usual armrest and oddments tray). And red "CS" badging features on the instrument panel and between the bucket-style seats in the rear. The M seat belts feature red and blue contrast stitching that pays homage to the BMW M colours.
Market and Model
You'll need quite a lot more cash for this M5 CS. At the time of this test in Autumn 2021, the standard M5 Competition listed at just over £102,000. Whereas BMW wanted £140,780 from you for the CS version from launch. Still, lots of little details will make you feel better about that outlay.
Open the bonnet for instance and check out how the V8 engine here gets a bespoke BMW M Power cover made from exposed carbon fibre and bearing a full-colour M logo. Then look at those gold 20-inch wheels with their M Carbon ceramic brakes and note how the alloy rims are shod with Pirelli P Zero Corsa track tyres measuring 275/35 R 20 at the front and 285/35 R 20 at the rear.
CS-spec gets you piercing BMW Laserlight headlamps too, these featuring additional black shading. The L-shaped light tubes are unexpectedly versatile: as daytime driving lights and side lights, they shine in the familiar white, but when low or high beam is activated, they switch to a distinctive yellow tone that BMW M5 CS drivers can also see from the outside, when they unlock the car remotely, triggering the Welcome Light.The M5 CS is available in three different paint shades - 'Brands Hatch Grey' metallic or exclusive BMW Individual matt paint finishes 'Frozen Deep Green' metallic and 'Frozen Brands Hatch Grey' metallic.
Cost of Ownership
That small weight reduction doesn't help you with running cost efficiency of course. That's rated here at 25.0-25.9mpg (for combined cycle fuel economy) and 248-257g/km (for CO2). For reference, a Mercedes-AMG E 63 manages 26.2mpg on the combined cycle and 245g/km of CO2.
What else might you need to know? Well, routine maintenance is dictated by 'Condition Based Servicing' that monitors oil level and engine wear, taking into account how long it's been and how far the car has travelled since its previous garage visit. Like all M cars, this one needs a first running-in service at 1,200 miles.
On to the warranty package. BMW offers a warranty that lasts for three years, no matter how many miles you complete. You can also insure your car through BMW, though as most M5s will be funded with company money through a lease deal, this brokerage fees are likely to be bundled into that. If you're the one paying the premium, the M5 CS predictably sits in a top-of-the-shop group 50.
According to BMW, each M5 generation has brought us greater levels of technological innovation. That's one way of looking at it. Another would be to point out that only the first 'E28' generation version had a fully motorsport-tuned engine and that since then, we've lost the purity of straight-six engineware, the instancy and screaming character of normally aspirated power and what was once the founding tenant of BMW design, rear wheel drive engineering.
At the same time though, much has certainly been gained - as you'll discover at the wheel of an M5 CS. With the standard version of this 'F90'-series model, BMW's development team proved that an AWD M5 could still retain a rear-driven, enthusiast-orientated character. And they delivered a super saloon that's as happy collecting your dry cleaning as it is on the Nurburgring Nordschleife. This M5 CS would of course be even happier on the Nordschleife. But it's still the ultimate road going super saloon. As every M5 should be.
BMW M5 CS review by Jonathan Crouch