Which BMW 3 Series Is the Better Buy: the 330i or the M340i?

Is the BMW M340i worth the extra money over the 330i? We spent a week with each to find out.

bmw 3 series

When it comes to cars that can do it all, few carry the cache of the BMW 3 Series. Over the past 45 years, Bimmer’s compact car has blended performance, comfort and usability in ways that have made it one of the benchmarks other automakers aim for when developing their own sedans.

Still, like the BMW M5, the 3 Series has had somewhat of a rocky road in the last few years. The luster earned in earlier generations faded a little with the fifth-generation model of the early Aughts, then dimmed a bit more with the sixth-gen version that was sold for almost the entire current decade. While still speedy and luxurious, they were largely considered to have lost some of the style and joie de conduire that defined past versions. So when BMW revealed the all-new seventh-generation car at the Paris Motor Show last year, the world held its breath to see if those motor-loving Bavarians could bring back the magic.

The new model, known internally as the G20 generation, certainly has plenty of visual pizzazz; indeed, it’s perhaps the most aggressive 3 Series since the E36 that debuted during the first Bush administration. But with the new model also came a change in the powerplant department: whereas past 3ers had offered multiple power levels below the domain of the sporty M Division’s wares, here in the States, only one car would come without the 13th letter of the alphabet appended to its name — the 330i. The only more potent version would be the M340i, designed as a halfway point between the base car and the forthcoming M3.

BMW 330i: $40,750+BMW M340i: $54,000+

BMW 330i vs M340i: What's Different

As anyone with some basic knowledge of BMW nomenclature has probably figured out by now, the largest difference between these two 3ers is what lies beneath their hoods. Those numbers long since stopped corresponding to exact displacements, but bigger numbers still mean bigger engines: the 330i packs a turbocharged 2.0-liter inline-four making 255 horsepower and 294 pound-feet of torque, while the M340i uses a turbocharged 3.0-liter inline-six that spins up 382 hp and 369 lb-ft.

Further setting the M340i apart: a limited-slip differential for the rear axle, a stiffer suspension that gives the car a 0.4-inch-lower ride, and wheel camber revised for better grip. It also scores a distinct grille where the traditional upright valances have been replaced with odd shapes that, from a distance, vaguely resemble the dotted lines notating the different cuts of meat on a butcher’s illustration of a cow.

BMW 330i vs M340i: What's the Same

Apart from that, however, these two 3 Series models are about as similar as they come. Or rather, they can be, if you spec the 330i to match the M340i by picking the M Sport package, which includes a more aggressive front fascia, a sport-tuned suspension and variable-ratio sport steering (delivered via the same chunky steering wheel found in the M340i) for an extra $5,200.

Unlike the aggressive M Sport six-cylinder car, however, you can also opt to have your 330i in more sedate form; just opt for the Sport or Luxury packages, which also open the door to different paint and trim options you can’t have in the other version.

Both 3 Series models come with a sole choice of transmission (an eight-speed automatic) and the same two choices of driven wheels (rear or all four). Whereas Americans used to be able to choose between a wide variety of 3 Series body styles, the lineup has currently been culled down to just four-door sedans; coupes and convertibles have been rebranded under the 4 Series moniker, while the station wagon and the bloated Gran Turismo versions have both been tossed from showrooms. (Europeans, of course, can still buy a 3 Series wagon; perhaps BMW will take a page from Audi and bring the two-box 3er here at some point, but that seems unlikely for now.)

What’s That Mean in the Real World?

95 percent of the time, driving an M340i feels exactly the same as driving a 330i. Both 3ers are comfortable highway cruisers, as you’d expect of any car born in the land of the autobahn; even at speeds well above what your driver’s ed teacher would advise you to do, it’s rock-steady and reassuring.

My 330i had the M Sport package, and the resulting sport suspension meant it felt pretty much as capable as the M340i in the turns I pushed it through. Admittedly, I wasn’t pushing the cars anywhere close to their limits — I had passengers and cargo in the car both times I reached fun stretches of road — so it’s likely that the M340i would be more confident and rewarding at max attack than the lesser car.

Both cars suffer from the poor steering feel that’s an unfortunate characteristic of many BMWs today. While the helms are responsive, there’s little of the feedback that characterizes great steering and helps bring joy to the act of driving. So far as your hands are concerned, you might as well be turning a very fast-acting video game racing rig, not something connected to the front wheels.

Optioned up the way my test cars were, they both came with all the bits of high-tech frippery BMW has to throw at the 3er, too. The new Live Cockpit Pro is just a fancy name for the sort of reconfigurable digital instrument panel found on plenty of cars nowadays; it’s certainly clear and effective, though it does pack a couple of minor issues, like a tachometer that goes in a counterintuitive counter-clockwise direction and a theoretically-useful central display zone that can’t be used to show anything of actual use. And the gesture-based infotainment controls that let you change the volume or radio station with a wave of your hand remain one of the more delightful new features in the automotive space, even if they don’t work quite as reliably as you’d like.

The remaining five percent of the time, of course, are those moments when you’re driving with, as JFK would have said, vigah. 382 horsepower is nothing to scoff at, and nobody makes inline-sixes quite as smooth and delightful as BMW; pushing your foot into the accelerator produces a thrilling burst of fluid acceleration that’ll make you wonder if, like the Supra that shares an engine with it, this Bimmer is making more power than claimed.

Yet even that five percent isn’t as great a difference as you’d think. The limited-slip differential in back no doubt makes it faster around a track, but in the real world, the 330i feels plenty well-balanced in the turns. And the turbo four found beneath the lesser 3’s hood is no slouch; it’ll still zip from 0 to 60 miles per hour in five and a half seconds or less, which is fast enough to hurl you onto highways, around traffic and down winding back roads with glee. (Plus, it racks up far better fuel economy than the six-cylinder; Car and Driver found it averaged 42 miles per gallon at 75 mph.) The gearbox is every bit as clever as the M340i’s, leaping to the right gear whenever you need.

Granted, the four-cylinder engine lacks the characteristic purr of an inline-six, but that’s ultimately a minor concern for a sedan like this. A sweet engine note matters only for those few seconds you’re flooring it, and the 330i is quick enough that you won’t have to listen for long. Besides, if you really can’t stand it, that’s what the stereo is for.

Which BMW 3 Series Should You Buy?

Unless you’re planning on hitting the autocross or race track every couple weekends, it’s hard to see any reason to fork over an extra $10,000 or more for the M340i. That’s not a slight against the M Sport model; it’s more a credit to how solid the basic 330i is. It may not be the default choice in its class anymore — there are too many great competitors out there, from the Kia Stinger GT and the Genesis G70 to the Jaguar XE and the Alfa Romeo Giulia — but it’s still a solid choice for anyone looking for a blend of fun and practicality in their daily driver.

BMW 330i: $40,750+BMW M340i: $54,000+

BMW provided these products for review.

Advertisement - Continue Reading Below
More From Reviews