Designed to fit into a slot in the BMW M4 ziggurat between the still-on-sale M4 Competition Package and the now-out-of-production M4 GTS flagship, the new BMW M4 CS possesses bags of appeal for a keen driving enthusiast and it should prove a reasonably sound investment, given it will be production-limited. The good news is that BMW's M division has executed the formula to near-perfection, because this M4 is an exceptionally good performance coupe. The bad news is, we're a little bit confused by the whole purpose of the CS...
In the metal
The general, visually pleasing shape of the BMW M4 is more than familiar enough, so let's focus on the CS specifics. It gets its own form of front splitter and rear 'Gurney flap' spoiler, both made out of carbon fibre-reinforced plastic (CFRP), with the former item taking inspiration from the mighty M4 GTS's jutting chin addenda. The CS also has a single-vent CFRP bonnet like the GTS and, unlike regular and Competition Package M4s, it wears lighter forged alloy wheels finished in Orbit Grey and wrapped in the same sticky Michelin Pilot Sport Cup 2 tyres as the GTS. These are 19-inch items at the front, to preserve steering feel and sharp turn-in, and 20s at the back to promote traction on the driven axle. Finally, mere aesthetic garnishes are provided by the Organic Light-Emitting Diode (OLED) rear clusters of the GTS, as well as two new colours - San Marino Blue, which will be offered on all M4s from now on, and Lime Rock Grey, which is specific to the CS.
Inside, copious amounts of Alcantara and the racecar-like door cards (featuring little fabric pull loops embroidered with the M tricolour stripes; how cool?!) are borrowed from the GTS, as is the conceit of having the M4's special initials stitched into the passenger-side of the dashboard. These touches are enough to make the CS's interior feel considerably more noteworthy than the cabin of an M4 Competition Package. Having said that, items like the M Head-Up Display and the lovely Alcantara steering wheel with a 12 o'clock marker - both fitted to our German test car - will remain on the cost options list, which is a little bit naughty.
Beyond the visual alterations, what we have here are a lot of software updates - and the pervading feeling that this car has been very, very carefully engineered to fit into an extremely tight gap in the M4 hierarchy. Although the wheels and tyres are different, and BMW M has fiddled with the CS's exhaust, and there's the use of carbon on the outside, the fact is that the car you are looking at here is essentially an M4 Competition Package with a remap and an Adaptive M Suspension software patch to compensate for the additional grip provided by the Michelin rubber. Nothing else has changed - and carbon ceramic brakes, also fitted to our test car, are another (pricey) item that will remain on the options list.
The outcome of all this is an M4 with 460hp and 600Nm, figures that are 10hp and 50Nm up on an M4 Competition Package, and 40hp down on a GTS with the same torque. The CS therefore has a 3.9-second 0-100km/h time and a top speed limited to 280km/h. As it's fitted with the M DCT dual-clutch transmission as standard, that compares to 3.8 seconds and 305km/h limited for the similarly DCT-only GTS, and 4.0 seconds and 250km/h limited for the M4 Competition Package with the option of DCT. See how tidily the CS slots into the M4 firmament?
Driving it
There are no complaints from us about the way the M4 CS drives. Unlike the regular 431hp car, which some on the team (me included) have always found a bit wayward, the CS has oodles of grip at both ends and a sense that, while possessing a chassis that requires treating with respect, this M4 is nevertheless vastly more capable than the standard car.
The standout details are the front axle, which is almost dementedly keen to slice into corners for the apex, the increased driver confidence brought about by the additional grip of the Cup 2s, the revised adaptive dampers and the lovely, lovely steering. Admittedly, on this last score, the CS is better in mid-ranking Sport mode, rather than full-on Sport+, where the steering is overly weighty and lacking in feel. There are occasions where you sense an excess amount of weight transfer, which can lead to backing off the throttle when it's not necessary, but in general even timid drivers should be confident that the CS is going to grip and go where it's intended to. The BMW's chassis is a peach.
And the drivetrain is fantastic, the GTS-matching 600Nm really giving the M4 CS notable extra strength at the sort of speeds that are only appropriate on race tracks or Autobahns. Nevertheless, we love the way the CS goes and, as some welcome extra good news, it sounds epic too. It's not as harsh, spine-tingling and racer-loud as the GTS, granted, but with a rumbling lower timbre and a lack of synthesised engine noises higher up the rev range, what you've got here is an M4 that no longer has a dull voice, as the Competition Package still does.
Everything else that marks out an M4 is preserved in the CS, so it's the sort of machine that you could use on a daily basis, which is definitely one area where it's ahead of the GTS. Overall, as a package, the CS is an absolutely grand performance coupe that should thrill its driver far more often than it frustrates, so we're delighted the company took the decision to bring it to market. And on that point...
What you get for your money
This is the big area for discussion. BMW Ireland has confirmed that the on-the-road price for the M4 CS will be €158,690. For a car that's mechanically no different to an M4 Competition Package.
You're paying for the modest engine upgrades, the carbon fibre, the Alcantara inside and the wheels, but it still feels like an awful lot to charge for the CS, if you ask us. It will, however, be limited in numbers, although right now BMW isn't putting a figure on precisely how many will be made. The German company is instead saying it will take as many orders as it can for the CS between now and 2019, with production capacity ultimately limiting how many will hit the roads. So there's the potential for the CS to be an investment piece that will appreciate in the mid-term, but by how much it might go up in value is difficult to say.
And if you start fitting carbon ceramic brakes and Alcantara steering wheels and the M HUD and so on to the CS, then you're going to be looking at a car - related to a BMW 420d, lest we forget - that's getting close to €200,000. Yikes!
Summary
The BMW M4 CS is a wonderful creation. It steers and goes magnificently, it has a belting soundtrack, it looks fantastic and it's a most welcome addition to the fabled M Cars canon. And yet... we're struggling to get our heads around this newcomer. There's a huge price premium to pay on it, over and above an M4 Competition Package Coupe with the M DCT gearbox fitted, and the resulting CS doesn't feel massively different in terms of the drive as a result. It's a bit sharper and a bit quicker, yes, but not so much as you'd easily notice; that being a direct corollary of the CS using almost all the same hardware as the Competition Package.
On the other hand, despite borrowing heavily from its more exalted sibling, the CS is nowhere near as special to be in nor drive as a GTS. OK, the 500hp M4 was farcically expensive and getting hold of one now is going to be next to impossible without paying way over the odds for it, but the end result is well worth it.
If the CS were a bit cheaper, fitted with the carbon ceramics as standard, or was guaranteed to be built in numbers of less than, say, 2,000 units, we might be completely convinced by it. As it is, we think it's a little too expensive and a little too similar to an M4 Competition Package for our liking. Which shouldn't detract at all from the fact that, from an engineering perspective, it's a corking performance coupe.