BMW M Battle: CS vs GT4 at Phillip Island

Back in the '70s, the BMW's Motorsport division was officially born with the inception of the legendary 3.0 CSL, or "Coupe Sport Lightweight".

A set number of homologation special E9 Coupes were stripped down and lightened to allow the marque to meet racing regulations for the European Touring Car Championship. The CSL soon became a cult classic, and earned the nickname of "The Batmobile" for its big bonnet fins, front air dam and striking ducktail spoiler.

And here’s the twist: the CSL didn’t come from the "M" Motorsport division. The CSL basically started it all. The M motorsport badge was then stamped on these sharper, high-performing versions of staple sedans and coupes, denoting their performance underpinnings and abilities.

Jump to modern days, and the M badge still means motorsport, but it can also mean “more”. More luxury, more tech ... more weight. Incredible cars – but not the lean, raw bruisers they once were.

The BMW M2 CS, M4 CS and M3 CS Touring. Photo: Supplied

So in 2017, BMW filled the widening gap between the softer M Competition models and the bombastic CSL, creating a middle ground for the motorsport enthusiast who wants to run some serious laps on the racetrack, as well as the road, with the CS, or "Competition Sport".

Launched in 2017, the M4 was the first to get CS treatment, removing some of the tech bloat and luxury appointments to lighten the load, but retaining the special feel with lashings of carbon fibre, swoopy spoilers and splitters, race seats, and of course more go from that unbelievably malleable 3.0-litre twin-turbo six-cylinder.

Versions in the M3, the M2 and the M5 followed suit, and in 2026 we have a new M2 CS, the most accessible in the range from a price point of view. 

So, what does CS really offer to the driver over the standard M badged versions, and how close is it to that performance car unicorn: the race car that performs just as well on the road? We set out for Phillip Island to find out – and put the CS range to the ultimate test against the GT racecar, the M4 GT4.

The M4 CS hit Australia in 2025 as a two-door performance car wrapped in carbon and priced from $254,900 before on-road costs. That is nearly $70,000 more than a standard M4 Competition.

It uses the same 3.0-litre straight-six engine, producing 405kW and 650Nm. Power goes through an eight-speed automatic and all-wheel drive, but the system can be switched to rear-drive too. It accelerates from zero to 100 km/h in 3.4 seconds and zero to 200 in 11.1, with a top speed of 302km/h.

BMW dropped 20 kilos (down to 1755kg) by using a carbon roof, bonnet, splitter, mirrors and diffuser. A titanium exhaust trims a few more kilos. Inside, the centre console is carbon with a 'palm rest' and small cubby over a storage console.

The BMW M4 CS. Photo: Supplied

The car comes with forged wheels, Michelin Cup 2 tyres and M Compound brakes as standard. The engine mounts are stiffer, and a massive aluminium strut brace caging the engine is standard.

Visually, the CS really stands out; there is a unique grille, yellow daytime running lights, red-outlined badges and 3D laser tail-lights. Paint options are Riviera Blue or Frozen Isle of Man Green.

Inside, heated M Carbon seats, an Alcantara wheel and carbon accents reinforce the performance focus. Some convenience features are removed. Adaptive Cruise Control, lane centering and automatic parking are not included.

The M3 CS wagon is most pragmatic of the bunch – providing your definition of practicality is the ability to haul a week's worth of groceries at 300km/h.

Mechanically matching the stats of the M4 CS on engine, power and torque, its big booty adds 0.1secs to the official 0-100km sprint when compared to the M4 CS (3.4sec vs 3.5secs).

The BMW M3 CS Touring. Photo: Supplied

The M Division shaved 15kg from its frame with the use of carbonfibre reinforced plastic (CFRP) on everything from the bonnet and front splitter to the center console and shift paddles.

Further CS treatment includes its CS-unique kidney grille, a high-gloss black roof spoiler with a cheeky red surround, and those lovely GT racecar inspired yellow LED running lights.

Exclusivity comes at a price, as again like the M4 CS, only 55 units were brought in at the start of 2025, at a cost of $253,900.

The new kid on the block is the baby M2 CS, which will not be limited in numbers, but may not be a massive seller as it is more expensive than a regular M4. The trick is it tips the M4 on performance, and also boasts those special CS extras.

Under the bonnet sits the same 3.0-litre twin-turbo straight-six, delivering a lesser 390kW and 650Nm, and sent to the rear wheels only. Zero-to-100 km/h is clocked in 3.8 seconds. The exhaust is four pipes with titanium mufflers and active flaps, everyone hears you coming long before they see you.

The BMW M2 CS. Photo: Supplied

Carbon roof, mirrors, diffuser, and a ducktail boot lid nod to the CSL’s heritage, and help to bring the weight 30kg lower (to 1700kg). Suspension is lower, brakes are sorted, and with the optional carbon-ceramic brakes priced at $19K, the stopping power is serious.

Inside, carbon trim, heated M Carbon seats, a big Alcantara steering wheel with a red 12 o’clock marker, and space for a race harness if you like.

The cost of this CS speciality is $172,900 before on-roads. That’s a leap over the standard M2 priced at $128,100, but remember, it leapfrogs the normal M4 in both performance and price.

The GT4 is a proper race car built by BMW Motorsport. It has the same engine as the CS cars, and the same maximum power, but sheds over 300kg by stripping out the luxury – though it still has air conditioning – and adding lightweight safety tech and componentry. This is a proper, red-blooded race car that’ll give our road cars a serious run for their money.

The BMW M4 GT4 EVO. Photo: Supplied

Behind the wheel - and with a conspicuous yellow L Plate on the windscreen – is the GT4's driver, Jay Murray. The 17-year-old racer debuted partway through last year in the Australian GT4 series after graduating from karting, and has recently travelled to Germany for the BMW M Motorsport Academy.

We lined up three of the CS cars on the main straight at Phillip Island, the track sweeping alongside the sea with that incredible view that never gets old. The M4 CS, M2, and GT4 sat side by side, engines warm and humming, tyres cold.

The M4 CS was kept in all-wheel drive for the launch. It crouched like a cat, backside low, then fired off the line. The GT4, on full slicks, was tricky to get moving, while the M2 reacted quicker off the line. But once the M4 was rolling, it was gone.

Near the finish, the M2 started to reel it in, the driver clearly nailing the shifts and the tiny timing differences that matter in cars like this. With machines this precise and this fast, timing is everything. Hit the paddle the instant the shift light flashes, or the limiter will bounce and cost you tenths, even seconds.

Besides, this driver was watching the numbers climb exponentially and the crest was fast approaching; may have backed off the thottle a tad before the finish line.

A fraction behind in third was the GT4 race car, with full slicks and a hard launch hampering its progress. Though there is no doubt the race car would whomp us all in the next test: timed laps around the track.

Our road (and race) cars were then put to the test against the stopwatch with Jay behind the wheel. The rear-wheel-drive M2 on full push looked like a handful, but the brakes and ceramics helped, and it crossed the line at 1:47.4.

The big M4 came alive at high speed. All-wheel drive, more power, a tad more weight, but still clocking a quicker time than the M2 at 1:46.87.

Then to give the road cars more of a chance, I added 70kg to the M4 GT4 by jumping in shotgun. It was futile: despite the additional ballast, the GT4 was on a performance-mapping free of its usual GT4 category restrictions, and it carved 10 seconds off the road cars with a 1:36.41.

But the GT4 goes back on the trailer, and we get to drive these CS cars home and make use of them in the real world. But which one to choose? And which one would you take home?

Check out the video for our conclusion, and drop us a comment with your own preference.

Samantha has been obsessed with cars and combustion engines for most of her life, and has spent the past 25 years deep in the automotive and motorsport industries. An automotive awards judge, rally driver and motorsport tragic, she spends weekdays writing about cars and weekends off-road, off-grid or running amok at the track.

Read more about Samantha Stevens