BMW 320d vs BMW M Models

What's the difference?

Despite BMW's wholehearted embrace of the SUV its 3 Series is still a critically important model for the brand in Australia. And this new version certainly has the spec and tech to take the fight up to Merc's C-Class. And if you're in the happy position of making that choice, it's now a whole lot harder. For our money the 330i marks the sweet spot with extra performance, safety tech and standard features for only a fraction more than $3k over the 320d entry-point.

Brutal, bruising and utterly brilliant, the M4 CS will be an acquired taste due to its no-compromise approach, but those willing to take the leap will find a performance car like few others at their disposal.

At just over 4.7m nose-to-tail the new 3 Series has crept 76mm in overall length but that dimension is still more than 200mm shy of its next-size-up 5 Series sibling.

Changes to the exterior design are more evolutionary than revolutionary. You're never going to mistake this car for anything other than a BMW 3 Series.

But even if the face is familiar, aerodynamic efficiency is outstanding. BMW admits its claimed Cd of 0.23 was achieved with a base model running on 17-inch wheels (not offered here), but even if bigger rims knock a few fractions off that number it's still an amazing result for a conventional four door sedan.

Big contributors are a full width front spoiler, 'air curtains' managing flow around each corner of the nose, almost complete sealing of the largest areas underneath the car, and a functional rear diffuser section.

The signature kidney grille has grown and is delivered as a single piece, with active shutters incorporated to manage cooling air flow through to the engine. Twin adaptive LED headlights (standard on all models) feature a sharp notch on their lower edge, a big clue for new model spotters.

Broad, carefully managed surfaces characterise the bonnet and flanks of the car, with a distinct character line just above door handle height enhancing its confident stance.

The slightly smoked L-shaped LED tail-lights sit proud of the body, and 18-inch alloys are standard on the 320d, stepping up to 19s on the 330i.

The interior has been redesigned with revised controls and new materials, including slick 'aluminium teragon' finish on the console and dash in the M Sport.

As you can see in our interior images, it's been tidied up and simplified considerably, although it will still be instantly recognised by current BMW drivers.

Highlights are a 12.3-inch configurable digital 'Live Cockpit Professional' instrument display (lifted directly from the X5), a new 10.25-inch media touchscreen and a standard (larger) head-up display.

The M4 CS is familiar in all the right ways, but definitely looks significantly jacked up compared to its lesser siblings.

Part of that is the extensive use of carbon everywhere, from its bonnet panels to its roof, front lip, side skirting and boot spoiler. But also because of its super-muscular angles and creases, including the huge dome in its bonnet.

Also exclusive to this M4 CS is the light treatment, with the front LEDs lighting up with yellow highlights the brand says are supposed to be reminiscent of GT racing cars.

At the back, the rear lights are flush with fibre optic lighting, lending a flowing and unique light signature that looks epic at night.

Inside, it's a sea of carbon, with the lightweight racing seats, the dash inserts and the centre console all lined in it. It is a perfectly finished space, though, and one that's also flecked with red, including a 12 o'clock band on the thick-rimmed steering wheel, the seat backs, the contrast stitching and the paddle shifts.

Be warned, though, it takes some acrobatics to climb into or out of the CS. The seat bottoms have these super high edges that double as grab handles, but require some awkward contortions to navigate.

In short, it looks angry, this M4 CS, inside and out.

A longer wheelbase (+41mm) has helped increase overall cabin space and rear room specifically.

There's plenty of storage provided with a large lidded box between the front seats as well as two large size cupholders in a recessed section in front of the gear shift (which can be closed off with a roll-top style cover).

The glove box is large and there are big bins in the doors with separate holders for full-size bottles.

Rear legroom is generous. At 183cm, sitting behind my own driving position, there was plenty of fresh air between knees and seatback, with lots of foot room to boot.

Headroom was more marginal with a straight back leading to a bonce/roof interface. But there are adjustable rear vents, twin cupholders in a fold-down centre armrest, and big bottle holders in the doors. Multiple USB ports (Type A and Type C) and a 12-volt power outlet are provided front and rear.

The boot space offers up a 480-litre luggage capacity with a 40/20/40 split-folding rear seat increasing cargo flexibility. Local towing capacity is yet to be confirmed, but indicative (European) ratings for both models are 750kg for an unbraked trailer and 1600kg braked.

Standard rubber is run-flat so there's no spare of any description.

It all boils down to how you classify practicality in a car like this. I mean, the basic stuff is all there – it's got two doors, four seats and a boot capacity of 440 litres.

It measures 4801mm in length, 1918mm in width and 1399mm in height, and room for front seat riders is good, but less so for anyone you squeeze into the back. There are even ISOFIX points for a child seat.

But if you consider practicality the practical pursuit of performance, then the M4 CS has plenty of perks.

We're talking a $254,900 entry price for the M4 CS, which – despite my attempts at justification – is a lot. Remember, the regular M4 is $168,700, and the M4 Competition is $186,500, so we're talking a sizeable premium here.

BMW justifies that price increase in two ways. The first is scarcity, with the M4 CS limited to just 50 examples in Australia. And the second is by dialling up every aspect of the M4's performance to terrifying levels.

The engine outputs are up, the weight is 20kg down, there are better brakes, better seats, a louder exhaust, a stiffer chassis – it goes on and on.

We'll get to some of the performance stuff in a moment, but here's what else your money buys you with the M4 CS.

It starts outside with staggered alloys, 19-inch up front and 20-inch at the rear, wrapped in track-ready rubber. There's also hi-po 'M Compound' brakes with red calipers, lightweight carbon racing seats that are heated up front, an Alcantara-trimmed steering wheel, the 'M Carbon' exterior package with carbon bonnet and roof, adaptive 'M Suspension' and a titanium exhaust that howls like the winds of hell.

The less performance-focused stuff is similar enough to the other M4 models including a 12.3-inch centre screen with digital radio, Apple CarPlay and Android Auto, a second 14.9-inch screen that handles your driving data and a head-up display. There's also twin-zone climate control, Merino leather upholstery and ambient interior lighting.

But all of that is secondary, really. This is about performance, specifically of the brutal kind.

The 320d is powered by a 2.0-litre four-cylinder twin-turbo-diesel, featuring common-rail direct-injection and variable inlet timing. It produces 140kW at 4000rpm and 400Nm between 1750-2500rpm.

The turbo's multi-stage design incorporates a small, high-pressure, fixed-vane turbocharger as well as a larger, low-pressure, variable-vane turbo to maximise response, performance and efficiency.

A 2.0-litre single turbo-petrol four-cylinder engine sits under the 330i's bonnet incorporating direct-injection, as well as variable valve and cam timing. Peak outputs are 190kW from 5000-6500rpm and 400Nm between 1550-4400rpm.

Mark the date because this is the first time the BMW 3 Series has been offered in Australia without a manual gearbox option. Both launch models send drive to the rear wheels via an eight-speed automatic (with wheel-mounted shift paddles) only.

BMW has found yet more grunt lurking in its trusty 3.0-litre 'M TwinPower' six-cylinder petrol engine, with the M4 CS now pumping out 405kW and 650Nm.

That's a decent jump from the 390kW and 620Nm served up by the M4 Competition, and a giant leap from the outputs of the 'base' M4 – 353kW and 550Nm.

Predictably, then, the CS is the fastest of the lot, knocking off the run from 0-100km/h in 3.4 seconds, compared to 3.5 and 4.2 in the Competition and M4, respectively. The top speed is also dialled up to 302km/h.

All that power is channeled through an eight-speed automatic and sent to all four wheels on demand, with the help of an 'Active M Differential'.

Despite each car's performance potential claimed fuel economy for the combined (ADR 81/02 - urban, extra-urban) cycle is commendably low.

BMW says the 320d delivers excellent diesel fuel economy, consuming a miserly 4.5L/100km, emitting 119g/km of CO2 in the process, with the 330i's fuel consumption figure coming in at 6.4L/100km and 147g/km.

You'll need minimum 95 RON premium unleaded in the 330i, with both petrol and diesel requiring 59 litres to fill the tank to full capacity.

The M4 CS is fitted with a 59-litre fuel tank, which – given the BMW's official fuel claim of 10.2 litres per hundred kilometres – should deliver a driving range on a full tank of 541 kilometres.

But... BMW also says the regular M4 – you know, the one that makes 52 fewer kilowatts and 55Nm less torque – uses 10.1L/100km, so do with that information what you will.

First, the performance figures. BMW claims the 320d will accelerate from 0-100km/h in 6.8sec, which is agreeably quick, while the 330i knocks that down to 5.8sec, which is properly fast.

Both engines deliver the same 400Nm of maximum torque at low rpm; 1750-2500rpm for the 320d, and a broader 1550-4400rpm spread for the 330i. Mid-range acceleration is strong and satisfyingly linear in each, the 330i that bit more urgent at the top end.

The eight-speed auto is velvety smooth, with the wheel-mounted shift paddles on hand for rapid 'manual' changes. Engine noise is muted at low revs but nice and rorty under pressure.

A stated aim in the development of this 3 Series was "dynamic engagement", and the standard strut front, multi-link rear suspension has been tuned to reinforce the driving part of the brand's long-standing 'ultimate driving machine' promise.

The standard suspension includes tricky two-stage dampers front and rear, but with all cars at the local launch fitted with the optional active damper system we'll have to wait to report on its quality (or otherwise).

This car's centre-of-gravity is 10mm lower than the model it replaces, which may not sound like much, but in engineering terms, absolutely is. In concert with a perfect 50:50 front-to-rear weight distribution, and wider tracks front and rear, it helps deliver an overall planted feel and predictable cornering balance.

The electro-mechanically assisted steering is accurate and linear with good road feel, which is not always the case in recent Beamers.

The launch fleet was also rolling on 19-inch rims (standard on 330i, optional on 320d) shod with Bridgestone Turanza run-flat rubber (225/40f - 255/35r) and despite that type of tyre's reputation for harsh characteristics and a moderate level of road noise, ride comfort on the typically coarse rural roads we covered in the Victorian high country was impressive.

Braking on both models is by ventilated disc front and rear, and even in spirited cornering maintained their power and efficiency. The M Sport brake package fitted to the 330i dials things up with four-piston alloy calipers (sourced from Brembo) up front.

The standard sports steering wheel is fat and grippy, the sports front seats combine firm location with long-distance comfort and overall noise levels are low. Overall, this is a super-impressive touring car.

The hardest and angriest M4 of all time is, perhaps unsurprisingly, hard and angry. This is a race track specialist, but because I don't happen to own one of those, my first experience with the barking (and barking mad) M4 CS was navigating my way back from BMW's inner-city dealership.

Like it or lump it, you're going to read some Porsche comparisons here, because you're talking not too far off base 911 Carrera money, and suddenly I find the two Germans doing battle for a spot in my dream garage.

First things first, the BMW won't be much chop for daily driving for most people. Happily, I have a sickness for uncomfortable sports cars. It tells me that no compromises have been made in the pursuit of punishing performance.

A good thing, too, because the BMW, at city speeds, can be punishing. Everything feels heavy, the seats aren't overly comfortable – especially the hard bits that tend to dig in when cornering – and it stiff-arms its way over road imperfections, that exhaust booming and barking as it does.

Again, I loved it, and you probably will, too. But it's still not the kind of car I'd relish sitting in the morning peak hour rush in.

But escape the confines of the city and the BMW M4 CS suddenly makes a whole heap of sense. The acceleration is genuinely brutal, and wonderfully theatrical, with that quad-tipped titanium exhaust barking and snarling as you rocket towards 100km/h.

The steering is brilliant, with feedback fed to your wrists via that thick-rimmed wheel, and the entire experience feels sharp, super engaging and edgy.

You can push the M4 hard and fast, and I'm certain my limited talents would run out far before the BMW's would, but there's this thrilling sense of peril sparked by the aggression of the experience, that I love.

It's like the magic of a roller-coaster, I guess. Even if you know nothing is going to happen, you never really know, right? And in that lies the magic.

But back to original question, this or a Porsche 911? There's no doubt a Carrera is a better all-rounder, in terms of comfy commuting and race track fun, but this angry M4 is all shouty theatrics, all of the time.

I bloody love it.

Expect no ANCAP rating here, I'm afraid. But the BMW 4 Series does wear a five-star rating from 2019.

The M4 CS gets six airbags (driver and passenger, side airbags, head airbags), along with what BMW calls its 'Driving Assistant Professional', which bundles active cruise control (with stop and go function), front and rear cross-traffic warning, 'Steering & Lane Control' and 'Lane Keeping with Side Collision Warning'.

BMW offers a three year/unlimited km warranty, which is drifting off the pace now with the majority of mainstream brands stepping up to five-year cover, with some at seven.

On the upside, bodywork is covered for 12 years, the paint for three, and 24-hour roadside assistance is complimentary for three years.

Servicing is condition based, so the car tells you when maintenance is required, and BMW offers a range of service packages in 'Basic' and 'Plus' grades up to 10 years/200,000km.

The M4 CS is covered by BMW's five-year, unlimited-kilometre warranty, with condition-based servicing available in packs, which will cost you $3530 over five years/80,000km, or $2900 over four years/60,000km.