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  • Miles Goodson

One Last Time...

The BMW M340i walks us down a narrowing path of the six-cylinder family executive.

blue BMW M340i

There has never been a BMW 3-Series without a three-litre straight-six engine, in the G20 generation the only one available outside of the M3 is the BMW M340i, and with the winds of change gusting it appears that this could be the last time a regular 3 series buyer will have the option.

The current range is almost entirely electrified, using either mild-hybrid technology in BMW 320i or the plug-in hybrid used the BMW 330e. The M340i uses the same 3.0 litre six cylinder engine found in the Z4 and Toyota Supra and churns out nearing 400 horsepower (officially quoted at 370bhp but the engine has been tested independently in a variety of application and achieved higher figures). Those wanting the same power in the coupe form can plump for the M440i if they don't mind the infamous grille.

There was a time when straight-six and BMW chimed together with the glowing chorus of a symphony hall at peak season. The most accessible BMW until the hatchback 1-series arrived in 2004 found its way to the home of millions, becoming the moneymaker before the BMW X5. A fitting send off the previous generation 1-series was the M140i which also received the same 3.0 litre engine as the M340i giving the last 1-series with rear wheel drive enough charisma and punch to outdo the competition from Volkswagen and Audi's convoluted 'S' range.

In a market overflowing with crossovers and SUVs the 3-Series remains the most important car that the company sell. The executive saloon market has seen little growth in competitors in the last ten years with the most notable addition being the Tesla Model 3, although most buyer's of a Tesla spend 5-series money or more, meaning the 320i and 320d still rule the company car market that usually caps the maximum value to entry level executive vehicles. A decade ago a six cylinder diesel was the no-brainer for many in Europeans, mixing power and efficiency with low taxation - oh how times change. The heart of the model line-up to which all these cars revolved around was the six-cylinder petrol 3-Series. An additional two cylinders meant something, either proof of your commitment to automotive enthusiasm, or a promotion opening up the company car list to the next level.

Purists could cry every time a 4-cylinder diesel rolled off the production line but as long as there was a 'true' BMW further along the line waiting to have its wheels bolted on their soul was soothed. Remember now that when the E30 M3 arrived on the scene it was graced with a four-cylinder motor, whilst the regular three series could be purchased in a variety of four and six cylinder variations, and so, as long as the six-cylinder survived, so did the concentration in the centre of the potion that dyed the BMW fanbase. The E36 and E46 M3 opted to go with six-cylinders as did the majority of the petrol options available for the saloon and estate of the regular 3-series. Then the E90 came along and steadily the straight-six began to go missing. The 3.0 survived, but by the end of the model run in 2012, it was the only one left standing. Onto the F30 and a change was afoot. No more naturally aspirated straight-six engines, a twin turbo that would morph into a twin scroll single turbo was offered for the 335i and 340i but turbocharged four cylinders dominated the lineup. Now in the G20 era, we see a whole new gauntlet ahead. The straight-six is put behind the nose of a single variation away from the M3/M4 badge. To those happy it is alive the thought has moved to the marketing buzzword of the day, electrification. BMW sell a range of plug-in vehicles, and plug-in hybrids, there are also 'mild hybrids' but the M340i has sidestepped the hype and BMW have stuck to the node of purity. It may be turbocharged but with driving dynamics that introduce power across the rev band, rather than dump it on the drivers lap few will mind. What is key is that this is likely to be the last time BMW will make such a car, the next generation six-cylinder 3-series, if one is made, will almost certainly have battery assistance, as is already offered in the current generation X5. Behind the wheel of a G20 M340i, you have to wonder if someone that owned one would ever want to change it. Offered in estate and saloon it is practical, the power is optimal for the road, enjoyable and outrageously fast when wanted. Adding more power would be absurd, the 370 horsepower on tap is probably a touch more than needed, although Alpina would argue and have given the B3 their take on a hot 3-series, 456bhp, and nearly 150 extra ft-Ib of torque. The trick the M340i pulls though is keeping the driver relevant, add another 200kg of batteries to make it more instantaneous in its reaction and it would lose the exact feeling that makes it so endearing. A human is just fast enough to react with the M340i, put add more systems to control the driving and the instant shove of batteries and it would feel like watching a movie at double speed, you still get an idea of what is going on, but you aren't savouring the moment any longer.

Aside from this internal fight for dominance between M-lite and M3 the M340i is still a great car

In a time when AMG are willing to throw away their USP and replace the head-banging V8's with four cylinders and F1 style KERS systems, it may seem silly to think that the M340i is the car that drivers want. The versatility and range aren't as good as if there was an additional battery pack. There is no 'smug silence' when crawling through traffic. Passing the neighbours at 5am is likely to get tougher as people demand nothing but a whirring noise from cars forgetting that only a decade ago it wasn't the rooster that sounded the beginning of a new day, but the clatter of a diesel engine as rush hour began. Neighbour mode for the most powerful and raucous petrol engines is a welcome addition for many, now able to enjoy sound without having to deal with discouraging looks from the curtain twitcher next door. Noise mandates on new cars will silence these further, making the death of an exhaust tune all but guaranteed unless an intervention is made.

Forgetting about societies whims for a moment leaves the curious reflection of a car in the office window, the M340i isn't perfect. For a start, the options available are more restrictive than a coupon at a theme park. No manual, which is a shame, BMW gearshifts may have always been a bit rubbery but an automatic with paddle shifters seems a bit like saying 'we offer fun, but it is organised fun'. Then there is Xdrive, many would opt for it anyway, but we are in a rare space of the market, there are those that would have loved a manual rear wheel drive option, and not just for us journalists to hoon about in. The M140i proved just how engaging this engine could be when tasked with fighting traction of rubber and road across a single axle.

Of course, this may start to tread on the toes of the M3 a little too much and that is likely why the edges have been smoothed for the enthusiast that opts to remain in the 3-series demographic, rather than an M customer.. Aside from this internal fight for dominance between M-lite and M3 the M340i is still a great car, despite not being perfect. On the road it gives the impression that it really wants to entertain but also takes life very seriously, the Xdrive is keen with its distribution of power, clearly, years of fettling the SUVs has paid dividends now. Step a toe too hard into a corner and you begin to feel an indication of slip through the wheel, but only on a damp road, in the dry, you would have to have a casual relationship with self-preservation to get slip. The controls are also class leading, forget the gesture controls and reach a cross over point in the Venn diagram of the latest technology and user experience. Need to turn down the radio whilst driving, the control wheel is there, want to select the appropriate raucous driving mode for a favourite bit of tarmac, it is nearly telepathic, other manufacturers could learn a lot as they delete buttons to save a few quid having to homologate them.

This then is likely to be the final chapter, the final six-cylinder BMW outside of the full M range and more interestingly the last time one is offered with only mechanical propulsion. Can BMW move on and keep its brand identifiable? That'll be a challenge, although as we see new design language, a pivot away from the past and a push toward a market that is content with the badge, the underpinnings may just be able to be moved without long lasting damage to the structure, for now, we'll enjoy the M340i, a true BMW, one last time.


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