2017 BMW M4 vs 2018

What's the difference?

The CS is a rocketship, no doubt, and it looks pretty incredible up close. Honestly, though, I’m struggling to see the value in an $82,000 leap from the Pure.

Factor in more expensive tyres – and different sizes at each end! – and little things like less robust interior trim, and the Pure starts to look like very good buying.

If you missed out on the GTS, the CS is a good substitute. If you’re looking for a BMW M4 that offers most of the bang for far fewer bucks, then the Pure is for you.

The BMW M4 CS is every bit as fast and engaging as you'd expect it to be. But be prepared for the day-to-day compromises that go with its pared back interior layout. It's beautifully engineered and dynamically excellent, but will have its hands full when Merc-AMG's similarly sized and priced (updated) C 63 S Coupe arrives shortly to rattle its cage.

Is the BMW M4 CS your kind of four-seat sledgehammer? Tell us what you think in the comments section below.

The M4 Pure looks all but identical to the M4 (and M4 Competition, if I’m honest), with the only real difference in aesthetics coming from the rim size and style.

All three feature an M bodykit that adds aggression and punch over a regular 4 Series, while the bulgy bonnet, quad exhausts and gloss black grille also tells people it’s no ordinary Bimmer.

The CS does step the game forward, with a bespoke front splitter in carbon fibre as well as a subtle rear end revision that includes the rear diffuser from the GTS under the bumper, and a small spoiler on the bootlid.

The M4 in either entry-level Pure, or next-step-up Competition spec already looks like John Cena in a 10-year-old's t-shirt, with muscular bumps, curves and cuts extending aggressively in all directions. From its bulbous 'power dome' bonnet, to the pumped-up guards and gaping vents, the M4 screams 'don't argue'.

But this CS version borrows heavily from the track-focused M4 GTS (phased out earlier this year) and dials the aggro up a few notches.

A Matterhorn-sized bulge in the centre of the lightweight CFRP (Carbon-Fibre Reinforced Plastic) bonnet descends towards a broad air extraction vent that could double as a stormwater drain in bad weather.

The front, exposed carbon splitter is a slightly less accentuated version of the GTS's race-ready set-up, and the signature kidney grille is finished in menacing gloss black.

That black finish, part of the standard BMW Individual 'Shadow Line' package, also extends to the side-window trim, window recess covers, and vents on the front wings.

CFRP (unpainted this time) reappears on the roof, and an exposed carbon Gurney flap-style spoiler adds a touch of flash and aero efficiency to the bootlid. A nice match for the carbon diffuser below.

Suitably wide black alloy rims (19-inch front, 20-inch rear) further enhance the intimidating look, with twin LED headlights and an 'Organic rear lighting system', the latter another lift from the GTS, delivering an impressively vivid display.

The interior is familiar BMW territory, but it does feel like you've had a nasty break-up and your significant other has filled the moving van with all the luxury bits.

The leather and Alcantara trimmed sports seats are classy and racy enough, but the door cards are made from a natural-fibre composite BMW calls 'Nawaro'. There are no storage pockets, and you get a webbing strap to help pull the door closed.

Super lo-fi, and bafflingly, the 'armrest' slopes downward at an angle that, despite an Alcantara-trimmed pad, makes it just about impossible to actually rest your arm on it. Perhaps it adds some wheel-twirling elbow room, but for the other 99 per cent of the time it's just annoying.

Although trimmed in contrast-stitched Alcantara, the centre console is also a rudimentary affair, with no storage box between the front seats or adjustable air vents for rear-seat passengers. It might be good for weight saving, but it's not so great in terms of day-to-day practicality (which we'll get to shortly).

There's more Alcantara on the M Sport steering wheel (a leather wheel is a no-cost option) and dash-panel insert, with the CS designation neatly called out in mosaic-style lettering near the centre stack.

The Pure’s front half makes for a comfortable and familiar location, especially if you’ve sat in a BMW over the last few years. It’s less ostentatious than the other M4s, too, with simple yet attractive cloth fabric, a leather-wrapped wheel and a restrained trim palette.

The CS steps things up a few notches, with literally metres of motorsport-spec Alacantara suede covering the inside, including the steering wheel. Our experience shows that suede wheels can wear more quickly with use, but they can be easily re-covered when the need arises.

The M-Sport front seats, too, are much more aggressive and sporty, but are still a decent fit even for the, erm, larger gentleman.

Both cockpits sling the driver’s seat low, and the steering wheel can be brought in close, making for an inclusive driving feel.

The two-door M4’s rear-seat area isn’t a focus for most buyers, but it is surprisingly difficult to access. There is a rear-mounted electric slider switch, but the seat-back latch is difficult to both grab and operate, and the seat moves forward very slowly. The high sill, too, makes rear access a tough task.

There are two ISOFIX points if you do want to bring kids along (good luck getting them in), and the seats drop down to extend the 445-litre luggage area.

There’s also space for two bottles front and rear in the Pure, a smallish stash space below the centre console and a lidded bin with a (kinda outdated) modular phone holder that requires the purchase of a bespoke bracket to suit your phone.

The CS must do without the bin, while its lightweight compressed-fibre door skins also forgo pockets and bottle holders. The door handles are also replaced with poorly placed racecar-spec fabric door pulls that make it quite an effort to actually close the door. Fashion over function of the highest order here (are you really saving that much weight over a door handle?).

There’s no spare wheel in either car, with a can of sealant and BMW’s Concierge services your only respite in case of a flat.

When it comes to cars, practicality is a subjective area. The M4 CS offers plenty of space for the driver and front-seat passenger, with room for two more in the back, as well as a decent boot. Practical, right?

But day-to-day details make all the difference and the drive to simplify the CS's cabin and reduce the car's overall weight has seen many common interior-storage options deleted.

The price CS owners pay for racy minimalism is a complete absence of door bins, no lidded box between the front seats, and no oddments tray in the middle of the centre console. Just a pair of cupholders ahead of the gearshift, and a shallow tray beyond that.

If you and a friend get into the car each carrying a standard load of personal junk like a phone, keys, wallet, and a beverage of some description, capacity is immediately exceeded.

Yes, you can shove all that 'stuff' into the (medium-sized) glove box, and that's probably the safer option anyway. But it's not as convenient as slipping things into strategically placed bins and boxes.

In terms of charging/connectivity there's a 12-volt outlet between the cupholders, and a single USB port oddly placed towards the rear of the centre console.

And while there are two seats in the back, getting to them requires the flexibility of a side-show contortionist, and the patience of a Tesla Model 3 reservation holder (the electric system that slides the front seat forward is glacially slow).

Even once you've managed to thread the needle through to the back, headroom is tight, so it's fine for kids and an occasional-only option for grown-ups. There are no cupholders or even a fold-down centre armrest back there, but there is a small, open oddments tray between the seats.

The boot offers a generous 445 litres of space and it's enough to easily swallow the CarsGuide pram or our three-piece hard suitcase set (35, 68 and 105 litres).

A cargo net is standard, there are four tie-down anchors, a small netted storage section behind the passenger side wheel tub, a cubby on the opposite side, shopping-bag hooks and conveniently placed handles, which release the 60/40 split-folding rear seat backs to liberate more room.

Don't bother looking for a spare wheel of any description. A repair/inflator kit is your only option.

In a classic less-is-more (money) scenario, the $189,529 BMW M4 CS cops a decent serving of standard features, but misses out on some of the luxury trimmings included on the next-rung-down M4 Competition ($156,710).

Standard inclusions run to adaptive LED headlights (including 'BMW Selective Beam' anti-dazzle tech), adaptive M suspension, combination 'Merino' leather/Alcantara seat trim, Alcantara-wrapped 'M' sports steering wheel (with blue/red stitching), a configurable head-up display, a 'BMW Individual' Anthracite roofliner, 'Comfort Access' (keyless entry and start), plus the 'iDrive6' multimedia system (managed via controller, touch or voice) running through an 8.8-inch, high-definition screen.

There are also big 10-spoke forged alloy rims, front-seat heating, sat nav, automatic headlights, rain-sensing wipers, front and rear park distance control, 'Surround View' parking assist, and the 'BMW ConnectedDrive' suite ('BMW Connected+' smartphone app, real-time traffic info, concierge services, and more).

That's a heavyweight equipment list for a car that's all about lightness. Inside, besides the basic door and centre console arrangement, the other significant concessions to kilo stripping are a 'specially adapted' 12-speaker version of Harman/Kardon's 'Surround Sound' audio system with DAB+ digital radio (16-speaker in the Competition), and a simplified, single-zone climate control set-up (dual-zone in the Competition).

Kind of like the CEO wearing a Swatch watch; they're wealthy and powerful, but 'all about performance', so they wear a functional, conspicuously un-flashy timepiece. They still live in a $10m penthouse apartment, though.

A new exhaust backbox, an ECU tweak and an extra dollop of revs to the 3.0-litre twin-turbocharged straight-six petrol engine nets the CS an extra 7kW of power over the Competition to push it out to 338kW at 6200rpm with a 7600rpm redline, and yields 50Nm more torque for 600Nm across a much narrower range of 4000-5380rpm.

The 0-100km/h dash for the CS is exactly 0.1 of a second quicker than the Competition at 3.9 seconds.

The Pure, meanwhile, makes 317kW at 5500rpm and 550Nm between 1850 and 5000rpm. It’ll do 0-100km/h in 4.1 sec in dual-clutch guise.

The lighter bonnet only gives the 1580kg CS a 5kg weight advantage over the Pure in dual-clutch spec, while the manual Pure is 20kg lighter than the CS, which can’t be had in self-shifter guise.

Like its E9 coupe forbear, the M4 CS is powered by an in-line six-cylinder engine, but things have moved on over the last 50 years, and the current (S55) engine offers a mechanical case study in the marriage of high-performance and efficiency.

The all-alloy unit features direct injection and twin turbos, the key drivers behind a stonking 600Nm of maximum torque (50kW up on the M4 Competition), available from 4000-5380rpm, and peak power of 338kW (+7kW), arriving at 6250 rpm.

It also features a 'charge air' (air-to-air) intercooler, 'Double Vanos' variable cam timing, and 'Valvetronic' variable valve lift (inlet and exhaust side).

The sleeveless cylinders use 'Electric Arc Wire Spray' technology to form a thin coating of iron on the cylinder walls, to save weight (no cast-iron liners) and reduce manufacturing complexity. And the engine's closed-deck design increases the block's torsional rigidity, enabling a substantial 10.2:1 compression ratio and use of a lightweight, forged crankshaft.

Transmission is a seven-speed 'M Double-Clutch' (M DCT) dual-clutch auto, complete with dedicated oil cooler, and drive is distributed across the rear axle via an electronically controlled, multi-plate 'Active M Differential'.

Interestingly, the more powerful CS claims a better combined fuel economy figure of 8.4 litres per 100km than the Pure, which returns a claimed 8.8L/100km on the combined cycle.

A 100km dash in the Pure netted us a dash-indicated figure of 9.1L/100km, while our CS test was a bit too short (and too track focused!) to effectively verify BMW’s claim.

Claimed fuel economy for the combined (ADR 81/02 - urban, extra-urban) cycle is 8.3L/100km, the twin-turbo six emitting 194g/km of CO2 in the process. 

Over roughly 350km of city, suburban and freeway driving (much of it 'enthusiastic') we recorded 10.9L/100km (at the bowser) An impressive number for such a strongly performance-focused machine.

Minimum fuel requirement is 98 RON premium unleaded, and you'll need 60 litres of it to fill the tank.

Both the Pure and the CS rely on BMW’s tri-mode adaptive dampers to give the car a different character when required, as well as an ‘All Ahead Full’ M button that can be set to a driver’s preference for throttle, gearbox, damper and steering modes.

Through town and out on the freeway, the M4 is pleasant enough in comfort mode, with a bit of tyre roar making its way into the car on rougher surfaces.

The Pure’s 19-inch wheels wear slightly taller-profile, less-aggressive tyres than the CS, which, combined with its lower engine output, gives the cheaper car a surprisingly more mellow demeanor overall. It’s not soft, mind you; it’s still pushing almost 500 old-school horsepower to the rear tyres, so there’s plenty on tap if you want to play.

Like the Competition, the CS shows a more mature side once the pace increases. The stiffer springs from the Competition and the more aggressive tyre set combine to reveal a complex damper map that can handle mid-corner corrugations and bigger hits with aplomb, while the chunky brakes are superbly modulated and offer incredible feel all the way through a big stop.

Both M4s come together beautifully on longer runs, with especially seamless flow through faster, longer corners. Ultimately, the M4 likes to be leant on a bit - but it takes a deep breath to trust it implicitly.

The steering, too, is still too digital and artificial at crucial moments. It turns in with aplomb and holds a line, but you’re not feeling it through your fingertips when you need it most, despite an array of electronic feels to pick from. Older M cars were far better in this area.

A few track laps confirms that the M4 is still a terrific toy, and that lack of linearity in the throttle map and steering don’t overly hurt its pace.

Let's get it out of the way. The M4 CS is fast. Anything running 0-100km/h in less than four seconds gains admission to a seriously rapid club, and BMW claims 3.9sec for this car (an exact match for the soon-to-arrive Merc-AMG C63 S Coupe).

We might have given the standard launch-control system a go, and may be able to confirm straight-line acceleration from step-off will compress your chest like an over-zealous lifesaver at CPR practice.

But just as impressive is the in-gear thrust, with 80km/h to licence loss (120km/h) covered in only 3.4sec. Which plays to the twin-turbo six's strength, with maximum torque arriving at a relatively high 4000rpm, and remaining on tap until 5380rpm.

Power doesn't reach its peak until 6250rpm, with the rev ceiling sitting at 7600rpm; impressively high for a twin-turbo engine.

We'd suggest it's best to keep the Sport+ suspension setting for track days unless you're already planning on replacing some of your older fillings.

Everything from the DSC, ABS, and active suspension to the active diff, electrically assisted steering and seven-speed, dual-clutch transmission has been tuned specifically for the M4 CS.

The 'M DCT' auto is agreeably civilised at parking speeds, yet shifts positively and rapidly, especially in manual mode, under pressure at higher pace.

An M Sport exhaust system features electronically controlled flaps sitting directly in front of the rear mufflers, and varies the intensity of the accompanying soundtrack according to drive mode and level of aggression. It sounds suitably angry, but those hoping for the soaring purity of say the (S54) naturally aspirated in-line six found under the bonnet of the E46 M3 will be left hankering for the good old days.

Front suspension is a modified MacPherson strut design, with a five-link set-up at the rear, and data from wheel-acceleration sensors on each corner is used to recalibrate each damper's setting every 2.5 milliseconds.

The drivetrain, suspension and steering can each be dialled into 'Comfort', 'Sport' or 'Sport+' modes, and the CS's ride changes markedly in the switch from Comfort to Sport; the former proving compliant and smooth rolling over rough city surfaces, and the latter keeping things reassuringly buttoned down on a B-road blast.

Although BMW says that, unlike the M4 GTS, it has deliberately steered the M4 CS away from a focus on the circuit (no roll cage, no adjustable splitters or spoilers) we'd suggest it's best to keep the Sport+ suspension setting for track days unless you're already planning on replacing some of your older fillings.

Speaking of track days, BMW says the M4 CS's dynamics were “honed on the Nurburgring Nordschleife” where it's recorded a best lap time of 7:38, which is as fast as a Ferrari 458 Italia and Lexus LFA. That's very, very impressive.

At 1580kg the M4 CS is 35kg lighter than the M4 Competition (1615kg), and just five kegs under the Pure (1585kg), so despite all the light-weighting hype it's worth remembering we're still looking at a car tipping the scales at just under 1.6 tonnes.

The electromechanical steering can also be tuned through the three performance modes, and Sport delivers the best combination of quick turn-in, agreeably linear assistance and decent road feel.

The standard M sport front seats look the part (the M4 logos in the backrest illuminate!)

But putting the CS's power down out of even moderately quick, tight corners is less convincing. The big forged-alloy rims (19-inch front, 20-inch rear) are shod with ultra-high-performance Michelin Pilot Sport Cup 2 rubber (265/35 front – 285/30 rear).

Squeezing the power in smoothly but quickly, the semi-slick tyres feel like they need more heat in them. Without going anywhere near the DSC's more taily 'M Dynamic' modes, and despite the active diff, the rear of the car will squirm when fed full throttle acceleration on corner exit, unsettling overall balance. Less edgy Michelin Pilot Super Sport tyres are a no-cost option.

The standard M sport front seats look the part (the M4 logos in the backrest illuminate!) and grip firmly without any discomfort for this 183cm tester.

And when it comes to slowing everything down, the standard brakes run to big ventilated discs front and rear, clamped by four-piston calipers at the front, and two-piston at the rear.

Our test example was optioned with the $15,000 'M carbon ceramic' package featuring humungous carbon rotors, thumping six-piston calipers up front, and four-piston rear. For that money you'd expect Le Mans-style braking performance, and while we didn't exactly put them to a 24-hour high-speed test, firm application of the left-hand pedal will consistently stand the car on its nose.

The BMW 4 Series (and by extension the M4 CS) hasn't been assessed for crash safety by ANCAP or EuroNCAP, but boasts a solid array of active and passive safety tech, with several notable omissions.

To help you avoid a crash the M4 CS features ABS, brake assist, EBA, EBD, 'Cornering Brake Control' (CBC), Dynamic Stability Control (DSC), Dynamic Traction Control (DTC) and dry braking, 'Emergency stop signal', lane-departure warning and a tyre-pressure-monitoring system.

M4 owners also receive a complimentary BMW Intensive Driving Experience course (one person per vehicle purchase), which is arguably the best crash prevention measure of all.

But significantly, there's no AEB (Auto Emergency Braking) or other, more recent safety bits and pieces (found on other current BMW models) like blind-spot monitoring, forward-collision warning, fatigue detection, reverse collision avoidance, or speed-sign recognition and warning.

If all else fails and a collision is unavoidable passive safety tech runs to head and side airbags for the driver and front passenger, as well as curtain airbags covering front and rear. But again, things like an active bonnet and active front head restraints, fitted elsewhere in the BMW world, are MIA.

There are ISOFIX child-restraint anchors with top tether points in each of the rear seat positions.

BMW also offers a Service Inclusive program for $3533, which covers everything – including spark plugs, brake fluids and other liquids – for five years or 80,000 km.

A more inclusive program that includes brake rotors, pads and clutch plates costs $8195.

A three-year free roadside service assistance program also covers the range.

Warranty cover is three years/unlimited km, with 24/7 roadside assistance included for three years, and additional support from BMW 'Servicemobiles' (07:00 – 23:00 every day) staffed by trained techs and stocked with key service parts.

Maintenance on all BMW 4 Series models is controlled by a 'Condition Based Servicing' system which piles real-time data (mileage, time since last service, fuel consumption, and how the car has been driven) into a specific algorithm to determine whether an annual vehicle inspection or (oil) service is due.