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by Mark Tisshaw 6 June 2023 Follow @mtisshaw Share
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Which way is the new BMW M3 CS going to go? Its bigger brother, the BMW M5 CS, is perhaps the greatest M car of the current era, a super-saloon that set new performance standards while retaining everyday usability. On that basis, much the same recipe in a smaller package opens up a path for another modern great to emerge.
Yet the M3 CS also shares much of its hardware with last year’s BMW M4 CSL, a fine car but not the icon of the duo of CSLs before it, the fact it was extreme neither here nor there.
Rest assured that the M3 CS “is the little brother to the M5 CS”, insists BMW M development boss Dirk Hacker, who says his team looked to simply “repeat the philosophy” that served them so well with the bigger car. The only real difference, he adds, is that one has eight cylinders and the other six.
A relief to hear, though you don’t have to drive too far yourself to realise that this is another monstrously capable car that seeks to serenade rather than scare you.
A disclaimer to start: we didn’t actually get to drive too far ourselves as this was the shortest of first drives in BMW’s first demonstrator, and we covered barely 30 miles. Still, even over this short drive a superb driver’s car was able to reveal itself, one that returns some of the deftness of M3s of old that’s always been lacking in the current-generation BMW M3 Competition.
With that in mind, you’ll recall we’ve been here before with M3 CS. When BMW last put a CS badge on the M3 at the end of the previous generation, a power boost of just 10bhp made the billing of it as a new version seem a bit arbitrary, and the type of special to shift the last bit of production at the end of a car’s life. Yet it was about more than the power: in becoming a CS and the numerous other chassis tweaks that went with it, it helped turn that M3 into a more playful machine.
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This time the power boost to its turbocharged 3.0-litre straight-six engine is 39bhp over the standard M3 Competition on which the M3 CS is based, taking it to the same 542bhp as the M4 CSL. This is achieved mostly by increasing the turbo boost by 0.4 bar to 2.1 bar and by some tweaks to the ECU.
The engine, torque for which remains at 479lb ft, gets stiffer mounts to better connect it to the body, and is hooked up to an eight-speed automatic gearbox driving all four wheels. There are some changes to the active differential to work with the power boost and the all-wheel-drive set-up is more rear-biased, though if you so wish you can make the car fully rear-wheel drive by turning the stability control off. Forgive your correspondent for not experiencing this with a queue of people to drive after me and on unfamiliar roads, though the M3 CS showed no ditch-finding tendencies…
Being all-wheel drive helps the M3 CS record a 0.3sec faster 0-62mph time than the rear-wheel-drive M4 CSL, at 3.4sec. A new titanium backbox is fitted for the exhaust, which sounds louder but not antisocially so over the M3 Competition.
The steering, chassis and suspension are also overhauled, Hacker saying changes to the shocks, coils and anti-roll bars in particular have all been done to increase the sportiness and track potential of the M3 CS while not removing the M3 Competition’s overall compliance.
The front alloys are 19in and the rears 20in, and both Pirelli P Zero and Michelin Pilot Sport 4 S tyres are offered, the latter being equipped to our car. Both feature simply to ensure a plentiful supply for buyers due to production demands. On that point, while the M3 CS is a limited-run model, a precise number has not been placed on it.
Those alloys are lightweight, one of a number of weight-saving features and parts on the car that save 20kg over the M3 Competition. These include a new bonnet, air intakes and splitter at the front, and a spoiler and whopping diffuser at the rear. A carbonfibre roof also features as standard, the material used liberally inside as well as to trim the likes of the shift paddles and the exterior mirror housings. Carbon-ceramic brakes are a £7295 option and were fitted to our test car.