Review: BMW 430i & 420i – The Non-Identical Twins

BMW is my marque.

A friend’s mother had an E34 M5 in Macao Blue with the full leather Champagne interior that quite literally spoke to me. Dad had an E23 735i in Polaris Silver that he and I spent many hours driving in the city and to various rural destinations – much to the bemusement of people in small country towns who thought we were mad driving a European saloon west of the Great Dividing Range.

I was reminded of these two cars recently when I was testing the new BMW 430i and 420i coupés.

The 4 Series nomenclature arrived in 2013 when BMW hived off the 3 Series Coupé/Convertible range into its own product line which included the coupé, convertible and (oddly) the 4-door Gran Coupé. The latest incarnation of the 4 Series arrived in the middle of 2020 with the G22/G23/G26 respectively, to a host of pursed lips thanks to the radical kidney grill re-design that made it from the concept car at the 2019 Geneva Motor Show through to production.

The BMW 4 Series Model Line Up

In Australia the 4 Series is currently made up of 8 models.

  • 420i M Sport (Coupé and Convertible)
  • 430i M Sport (Coupé and Convertible)
  • M440i xDrive (Coupé and Convertible)
  • M4 Coupé
  • M4 Competition Coupé

(A BMW M4 Convertible is on the way and will be available in 2022.)

The BMW 4 Series range is very broad and caters to every driving style. The 430i M Sport and 420i M Sport are right now the sweet-spot of sports-luxury coupé driving in what is a very competitive market. Driving these two models back to back over two weeks presented me with the perfect conditions to see if the latest coupés from Munich lived up to their place in BMW’s very rich 2-door history.

My only reservation was that in the past anything with a ’30i’ suffix was usually powered by a three-litre six-cylinder motor (hence the ’30’) and the 20i a smaller two-litre four-cylinder. This time it’s different. Both cars have the same 1998cc block, so I’m curious to see how the ‘same engine’ is capable of satisfying two different target markets and price-points.

The BMW 430i M Sport

Finished in Tanzanite Blue metallic with Vernasca Oyster leather trim and aluminium highlights, this is a very appealing colour combination. In addition to the standard M Sport package, this 430i was optioned with the Visibility and Comfort packages. Behind the wheel the experience is very BMW with the fully electronic instrument cluster using the right colours and fonts for the very easy to read dials.


I used to think that the modern Holden Monaro was the best proportioned two-door coupé in Australia, but I have to say the profile of this new 4 Series is just that little bit better. The lines from front to rear flow perfectly giving the impression that the car is longer than its 4.77m length.

The curvature of the roofline from the A-Pillar to the boot-lid is considerably smoother than the previous model and the C-Pillar now morphs into the rear quarter panel beautifully from any angle. So much so that from a couple of perspectives, the 430i possesses some Aston Martin DB9 visual characteristics.

The tail-light assembly is now almost all LED technology and sweeps from either side of the number plate to the outer edges of the rear which keeps the line from the bottom of the rear window to the boot-lid lip nice and low. The reversing camera is integrated into the BMW badge meaning fingerprints are less likely when opening the boot. Speaking of the boot, there is easily room for a couple of sets of golf clubs.

At the front, yes, the grille takes some getting used to, but you will learn to love it. The chrome surrounds on the 430i M Sport do draw attention to it. However, as you will see with the 420i M Sport below, the addition of a $500 option to extend the BMW Individual high-gloss Shadow Line to the kidneys does soften their appearance.

Elsewhere at the front, the BMW Laserlights are next-level in terms of nighttime visibility. The Auto High-Beam function on the indicator stalk activates lighting technology so advanced that it allows the lights to move independently of one another to quite literally “throw” light around other vehicles on dark motorways.

Other exterior joys of the 430i M Sport are the 19″ BMW Individual Bicolour light-alloy wheels that house trademark blue brake callipers front and rear.


Much like the exterior, the interior of the 430i M Sport has been updated to reflect the needs and wants of drivers in 2021. Beautiful lightness, near-perfect visibility, and a cockpit that for me felt as much a BMW as it was the first time I drove one nearly thirty years ago.

The completely digital dashboard is easily readable in any light and depending on the Driving Mode you have selected, provides you with the key information you need and nothing you don’t.

The electric seats for the driver and front passenger are very comfortable and thanks to lumbar support and multiple memory positions, your perfect driving position is only the press of a button away.

On our press vehicle, the gear-shift and BMW iDrive surrounds were finished in a blended aluminium treatment that did take the luxury feel of the interior down a little, but the upside is that it does hide fingerprints much more effectively than a black piano or high-gloss timber finish.

Rear-seat space is exactly what you would expect in a two-door coupé but unlike similar German coupés, minor movements of the driver and passenger seats will see space open up. Access however, does not improve.

What’s the 430i M Sport like to live with?

My experience with the 430i M Sport was all contained in the city. Lots of stop-start driving with precious few opportunities to open the taps. That being said, I found the 430i M Sport very easy to live with. Access was far easier than I expected with doors that are over 1.3m long.

Urban and country driving open your eyes to very different aspects of a car. As you will see below, country driving in the new BMW 4 Series is brilliant, and in the city, some of BMW’s best technology makes even the most mundane drive special.

As with all BMWs the driving position is perfect once you find it. The seats took a little getting used to and once I found my sweet-spot all was well in the world. Driver systems such as Active Pedestrian Safety and Adaptive M Suspension are excellent in the city where roads can be unpredictable and pedestrians can do anything at anytime. The Head-Up Display has been overhauled in the 4 Series and provides more information in perfect line of sight for the driver.

The steering is very light thanks to a completely electronic set-up and the 8-speed Steptronic gearbox is silky smooth and whilst it changes gears frequently in traffic, it does so with such velvety smoothness, you barely notice. As with most BMWs the braking is excellent and combined with the passive safety systems, even last minute emergency braking won’t put you through the windscreen.

Several cameras and sensors around the 4 Series take care of parking and the Parking Assistant Plus system brings it all together to take the stress out of parking. As I said above, the boot is commodious and thanks to the BMW aerodynamicists really easy to access with the low boot-line.

The 10-speaker sound system in the 430i is well above par and the addition of wireless Apple Car Play and Android Auto very much expected and enjoyed however, the Qi wireless charging pad did ‘cook’ my iPhone XS to the point that it overheated and shut down.

Smartphone cooking to one side, this is an exceptional mid-sized two-door coupé that has been improved brilliantly over the years to keep pace with the advances in technology and environmental needs. It’s just a shame that the three-litre six-cylinder engine couldn’t come along for the ride.

The BMW 420i M Sport

Following a week with the 430i M Sport – wafting around the city, I slid behind the wheel of its younger sibling thinking that it was going to be a week of comparisons and justifications. It so wasn’t.

The following day I headed 5 hours west of Sydney to enjoy Easter with a collective of school families. Thankfully, the trip meant that I’d pilot the 420i M Sport alone whilst the rest of the family made their way out bush in the family car.

After ninety minutes of mundane Good Friday traffic, I peeled off the Hume Highway to make my way northwest towards Cowra. As soon as the 100km/h limit came into effect on the north-side of Goulburn, the 420i M Sport came alive.

The 430i and 420i share the same 2-litre 4-cylinder B48 engine and thanks to exhaust and tuning mods at the factory, the 430i produces 195kW and the 420i a none-too-shabby 135kW. Whilst I thought I might not have been too smart scheduling my reviews of the new 4 Series in the order I had, it turns out that I may have accidentally discovered that a bit more oomph is more usable in the city and that less weight and better fuel consumption are better on the open road.

The single-lane road from Goulburn to Crookwell snakes through ‘Wind Farm Alley’ and across the Pejar Dam wall. This road has some lovely sweeping curves that the 420i M Sport just glides along – barely breaking a sweat.

Passing through Crookwell the road heads in a westerly direction and the next way-point of any significance is a town called Rugby. The 420i M Sport is now hugging the roads beautifully and thanks to double-demerits for the Easter long weekend, I’m not pushing the limits of this beautifully balanced coupé too much. Recent rain has chopped up the roads with some massive potholes needing to be avoided to save the rather low profile Bridgestone Turanza tyres front and rear.

The 420i M Sport is finished in Mineral White metallic paint and has been optioned with black 19″ Double-spoke M Light Alloy wheels and additional BMW Individual high-gloss Shadow Line treatments making the kidneys all black as well as the external mirrors and the rear around the twin exhaust pipes. It might only be a 420i M Sport, but this car looks and feels so different to the double-breasted Canali suit that I was driving around Sydney the week before.

Thanks to Waze, I obediently turn off the Crookwell to Rugby road onto what I suspect will be a little-known short-cut that the boffins at Google have calculated via AI will knock precious minutes off my ETA. Indeed it does until the bitumen disappears and the 420i M Sport is momentarily thrust airborne onto a couple of kilometres of freshly graded gravel road. In my mind I’m back in my father’s 735i blasting between Mendooran and Gilgandra late for a cattle sale.

The 420i M Sport is just as planted on the gravel as it is on the pot-holed sealed roads. Huge plumes of dust billow in my wake which are always satisfying. The DSC light flashes occasionally to let me know that the traction limits are being exceeded and BMW is keeping me safe and pointing in the right direction. I put the 420i M Sport into Sport+ mode for a moment just to feel the difference on an unsealed road. The attitude of the car immediately changes and I back off the throttle to prevent putting one of the best BMWs I’ve ever driven through a farmer’s fence and ruining his Easter.

I rejoin the Boorowa Road just west of Lost River and as the sun starts to set, I head for Rugby and then on to Frogmore and finally to my destination on the banks of the Lachlan River.

The interior of the 420i M Sport is as you might expect very different to the 430i M Sport. The seats are now a combination of Alcantara and Sensatec leather with contrasting blue stitching that shows glimpses of the famous M colours.

I’m now 4 hours into my journey and I’m comfortable without feeling too fatigued. The 2-zone Air Conditioning has kept the interior cool and fresh even on my short gravel detour. The low-profile Bridgestone tyres are performing brilliantly, although as the road flows north from Frogmore, the condition of the bitumen worsens and I start thinking about the last time I changed a tyre.

Then just as I can feel my attention wandering, one of the best driver-aids I have ever seen fitted to a car sprang into action. A three-minute “Vitalize” program was offered to me via the 10.25″ touch-screen Control Display. I was very curious. A swift press of the iDrive controller and the program commenced. What followed was transformational. The interior temperature dropped to 18C and the air-conditioning fan oscillated from full power to minimum and back again instantly increasing my attentive state. A meditative soundtrack started playing and for the next three minutes, I was completely refreshed and energised. What a stunning feature to have!

I arrive at our weekend destination and after being welcomed by our hosts I headed back out to the 420i M Sport to retrieve my luggage. Just like I had on so many occasions decades ago, I had very successfully repainted the front of a beautiful BMW with the carcasses of bugs – and just like then – they were a badge of honour for the joy I felt driving such a great car on some great roads.

I mentioned the fuel consumption earlier in this review. Below are the photos of the data from the 420i M Sport. That’s 1240.3km at an average of 6.3L/100km or 37MPG in the old money. Super impressive.

The BMW 430i M Sport – $111,505 drive-away.

The BMW 420i M Sport – $90,351 drive-away.

Both cars come with BMW Service for 5 years and 80,000km. More details at

About Author
Mike is the Australian editor of with a lifelong passion for cars, technology and engineering. He reviews and writes about all kinds of motoring and tech products for our readers. Follow Mike on Instagram or send him an email:
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