BMW 320d vs Mercedes-Benz CLA250

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.

The Mercedes-AMG CLA 45 S is more glorious madness from the hot-rodders in Affalterbach. A design and engineering master-class putting a slightly more mature spin on the fast and furious small AMG formula. But only slightly. It's brilliantly outrageous.

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.

Claimed to blaze from 0-100km/h in 4.0 seconds the second-generation CLA 45 has the performance credentials of a mid-engine supercar, wrapped in a relatively unassuming three-box body. And while it might look mild-mannered from a distance, this devil's differences are in the detail.

Like it's A 45 sibling the CLA 45 S features AMG's now signature Panamericana grille with 12 vertical louvres, a winged front spoiler treatment, extra aero bits around the front air intakes and 'Power Dome' bumps in the bonnet.

The side skirts are wider, and the 19-inch twin five-spoke rims are standard. While at the back the diffuser treatment is more pronounced than the hatch, but the fat 90mm exhaust pipes are the same, and the lip spoiler is on the boot lid rather than the roof.

The interior is virtually identical to the hatch, the biggest difference being the four-door coupe's frameless doors.

A combination of Merc's 'Artico' faux leather and 'Dinamica'  microfibre trim is accented with racy yellow highlights, with a nappa leather and Dinamica AMG Performance wheel and sports pedals completing the picture.

And the twin widescreen MBUX instrument and media display boasts AMG-specific read-outs on everything from gear selection, warm-up menu, car set-up, a G-metre, race timer and engine data. The standard 'Track Pack' even includes specific circuit layouts and data.

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.

At just under 4.7m long (248mm longer than the A 45 S hatch), a bit under 1.9m wide, and fraction over 1.4m tall the A 45 S in the dimensional bullseye for a compact four-door.

The CLA A 45 S driver is presented with the same sleek 'MBUX' widescreen display found in the Mercedes-Benz A-Class, and storage runs to two cupholders in the centre console, a lidded bin/armrest between the seats (including twin USB ports), decent door pockets with room for bottles and a medium-size glove box.

In a swap to the rear, sitting behind the driver's seat set to my (183cm) position, I enjoyed adequate knee and foot room, although headroom isn't as generous.

A centre fold-down armrest incorporates two cupholders, again there are generous pockets in the doors with room for bottles, and adjustable ventilation outlets are set into the back of the front centre console is a welcome inclusion. No map pockets on the racy, hard shell sports front seats, though.

There are three belted positions across the rear, but the adults using them for anything other than short journeys will have to be good friends and flexible. Best for two grown-ups, and three kids will be fine.

Boot volume is a healthy 460 litres (VDA), expanding further with the 40/20/40 split-folding rear seat down. There are tie-down hooks, a 12-volt outlet and elasticised storage pockets either side of the load space to further enhance useability. But beware, the Merc-AMG CLA 45 S is a no-tow zone.

The new CLA 45 is launching in the premium S variant only (a 'base' non-S version is offered in other markets). The outgoing model was tagged at $93,800, before on-road costs, prior to its discontinuation in January this year, and Mercedes-Benz Australia has hinted strongly that a price increase is likely. So, expect a list price in the mid-$90k range.

We'll cover active and passive safety tech in the safety section, and although final Australian specification is yet to be confirmed you can expect the stand ard features list to include the 19-inch alloys, 'Artico' faux leather and 'Dinamica' microfibre trim upholstery, the 'MBUX' widescreen cockpit display (two 10.25-inch digital screens) and 'MercedesMe' voice recognition, heated and electrically-adjustable sports front seats, auto adaptive LED headlights, LED tail-lights and DRLs, keyless entry and start, auto-dimming rear-view mirror, dual-zone climate-control, sat-nav, multi-function sports steering wheel, active cruise control, rain-sensing wipers, Active Parking Assist' (with ultrasonic proximity sensors front and rear), rear privacy glass, plus premium audio with digital radio, as well as Apple CarPlay and Android Auto.

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.

The A 45 S's all-new 2.0-litre (M139) engine is claimed to be the most powerful series production turbo four ever made, pumping out 310kW at 6750rpm and a monumental 500Nm, peaking between 5000-5250rpm. . That's up from an already impressive 280kW/470Nm on the out-going model.

It's an all-alloy, closed deck design fed by a combined direct and port fuel-injection system, with a single, twin-scroll turbo featuring low-friction roller bearings for quick spool up.

It's transversely mounted, but compared to the previous model has been spun 1 80-degrees on its vertical axis so the turbo's near the firewall and the intake system sits at the front to simplify and shorten ducting on the intake and exhaust sides.

The cylinder linings are treated with Merc's patented 'Nanoslide' coating, which delivers an ultra-hard, mirror-like surface for less friction and greater durability. And 'Camtronic' variable valve control sits on the exhaust side.

Drive goes to all four wheels via an eight-speed 'AMG Speedshift DCT 8G' dual-clutch auto, with manual shift paddles attached to the steering wheel.

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.

Claimed fuel economy to the combined cycle NEDC (New European Driving Cycle) standard is 8.1L/100km, the engine emitting 186g/km of CO2 in the process. Figures for the Australian (ADR 81/02) standard will be issued at the time of the car's local launch in early 2020.

Stop-start is standard, minimum fuel requirement is 98 RON premium unleaded, and you'll need 51 litres of it to fill the tank.

Our combination of furious hot-lapping on the circuit and relatively enthusiastic open road driving on the launch program means we'll wait until we test the car on home soil to log a real world average.

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.

Mercedes-AMG invited us to the Jarama race circuit just outside Madrid in Central Spain, and the twisting B-roads nearby, to sample its latest pride and joy.

In the AMG tradition the engine is assembled by hand, by one technician. And hats off to the spanner twirlers, they do a great job. It's a spectacular unit. Torque delivery is shaped to mimic a naturally aspirated engine, with the maximum figure arriving between 5000-5250rpm.

But that's not to say it's hollow in the mid-range. Around 90 per cent of that peak number is available from below 3000rpm and low-end throttle response is brilliantly crisp and linear, helped in no small part by roller bearings on the turbo for a quicker spool up.

Merc-AMG claims 4.0 seconds for the sprint from 0-100km/h, which is supercar fast and with drive going to all four wheels entertainment is the name of the game.

The eight-speed dual-clutch auto is positive and sharp, especially in manual mode where shifts flick through in much less than the blink of an eye.

And as the A 45 S beefs up the A-Class on the outside, it's the same underneath the skin with body reinforcement including an alloy sheering plate under the engine, a front strut tower brace, extra reinforcement between side members and A-pillars, and diagonal struts on the front and rear of the underbody.

So, the strut front, four-link rear suspension has an extra stiff platform to hang from, and the three-mode 'Ride Control' active damping can transform the ride from soft and compliant to tightly buttoned down.

The speed-sensitive, electromechanical steering is specifically tuned for this car, and it points accurately with good road feel and pleasantly firm weight in Sport and Sport+ modes.

Rubber is Michelin Pilot Sport 4 S, and it grips hard. On the fast and technical Jarama circuit they performed flawlessly, helping the A 45 S transform its prodigious power into maximum forward velocity without fuss.

The icing on the dynamic cake is 'AMG Dynamic Select' with six modes from 'Comfort' to 'Race' adjusting the engine, transmission, steering, suspension, and exhaust.

On top of that 'AMG Dynamics' uses the ESP and torque vectoring (by braking) to vary the level of stability and slip through four levels from 'Basic' up to 'Master'.

We played with all the toys including 'Race Start' and a 'Drift Mode' made possible by a new rear axle featuring two multi-disc clutches - one for each rear wheel.

Torque is split variably between front and rear axles with a default setting of 50/50 rising to around 70 per cent to the rear when pushing hard. Drive is also continuously managed across the rear axle, and like a swan gliding across the lake all the action happens seamlessly out of sight, turning you into a track hero in the process.

The first-gen A45's exhaust was a mass of pops, bangs and crackles, while this car's more rasping and rorty exhaust note is controlled by a flap in the system adjusted by engine speed and load. It's also amplified by the 'AMG Real Performance Sound' system, which puts some actual engine and exhaust noise (nothing is synthesised) through the speakers.

Open road ride comfort in the softest setting is surprisingly good, with rough surfaces unsettling the car only slightly despite the big 19s and high-performance rubber. Body control is S and S+ settings is spot-on, the car feeling planted, predictable and ultra-responsive on tight, twisting backroads.

Braking power is professional grade with six-piston calipers at the front and single piston rear, on vented and perforated rotors all around. Even following session after session on the track there wasn't a hint of fade.

Although final Australian spec is yet to be finalised, you can expect a host of active safety tech including ABS, BA, EBD, stability and traction controls, a reversing camera (with dynamic guidelines), 'Active Brake Assist' (Merc-speak fo AEB), 'Adaptive Brake', 'Attention Assist', 'Blind Spot Assist', 'Cross-wind Assist', 'Lane Keep Assist', a tyre pressure warning system, the 'Pre-Safe' accident anticipatory system, 'Traffic Sign Assist' and 'Adaptive Highbeam Assist'.

If all that fails to prevent an impact you'll be protected by nine airbags (front, pelvis and window for driver and front passenger, side airbags for rear seat occupants and a driver's knee bag), and the 'Active Bonnet' automatically tilts to minimise pedestrian injuries. A first-aid kit and hi-vis vests in the boot are thoughtful additions.

The A-Class was awarded a maximum five ANCAP stars in 2018, and for smaller occupants there are three child restraint/baby capsule top tether points across the back seat, with isofix anchors on the two outer positions.

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 Mercedes-AMG range is covered by a three year/unlimited km warranty, which, like Audi and BMW lags behind the mainstream market where the majority of players are now at five years/unlimited km, with some at seven years.

On the upside, Mercedes-Benz Road Care assistance is included in the deal for three years.

Service is likely to be scheduled (as per the out-going CLA 45) for 12 months/20,000km (whichever comes first) with pricing available on an 'Up-front' or 'Pay-as-you-go' basis.

For the first-gen CLA 45 pre-payment delivers a $500 saving with the first three services set at a total of $2950, compared to $3650 PAYG. Fourth and fifth services are also available for pre-purchase.