Believe it or not, the B58 inline-six has been in production for about a decade now. It debuted in the F30 3 Series, subsequently appearing in everything from BMW SUVs to off-road-ready trucks like the Ineos Grenadier and performance icons like the Toyota Supra—and nearly every niche in between, too. The 3.0-liter mill uses a single turbocharger to generate 300+ horsepower and close to 400 pound-feet of torque. It replaced the N55 engine, which itself replaced the twin-turbo N54 engine.
Those uninitiated may wonder: why does any of this matter? The B58 is a wonderful engine offering a great balance of smooth power delivery and perky off-the-line performance. But it’s also one of the most reliable power plants BMW has ever produced, standing the test of time and even holding up well when modified. Plus, with so many engines in circulation, replacement parts are relatively cheap and easy to find. Maybe all this talk has you looking for a new car. If that’s the case, we’re here to help – here are our top five picks for B58-powered BMWs.
BMW M340i
While the F30 3 Series 340i was the first 3 Series to get the B58, the G20 chassis arguably did it the best. Along with the complimentary M badging, early M340i models featured iDrive 7 and got considerably more (quoted) horsepower than the F30 340i models – 382 vs. 322 horsepower. It came in all-wheel or rear-wheel drive, too – xDrive cars offered zero to 60 acceleration that rivaled the outgoing M3 of the time (F8X).
The M340i – and its predecessors – are great because they fit into almost any lifestyle. Other than a missing manual transmission, enthusiasts will love the car. Its agile chassis responds great to modifications, and there’s a truly huge aftermarket. But even if you’re less enthusiastic, the M340i is a comfortable cruiser that makes cutting off other jerks in traffic, long road trips, and everything else easy.
BMW X3 M40i
If you love the M340i but need a little bit more space – or any towing capacity to speak of – the X3 M40i is the choice for you. Standard xDrive all-wheel drive allows the SUV to rip from zero to 60 mph in around four and a half seconds. It’s a step back from the radical X3 M but still offers much for enthusiasts to love. Towing up to 4,400 pounds makes it ideal for enthusiasts with passions outside of their daily driver, too.
Compared to the paltry 17 cubic feet of trunk space the M340i offers, the X3 M40i is positively cavernous. The X3 M40i’s 62.7 cubic feet of cargo space makes it great for hauling cargo. The fact that this – especially on the used market – affordable luxury SUV is a few bolt-ons and a tune away from 400 wheel horsepower only makes it more appealing.
BMW Z4 M40i
The Z4 M40i is an open-top Supra, and it gets even better with the recent introduction of the Handschalter Package. It adds a manual transmission and some special touches like exclusive trim and wheel options. The manual trans is definitely the highlight, but even without it, the Z4 M40i still shines. The potent engine and relatively light curb weight (just around 3,500 pounds) make it quick and fun.
We can’t recommend the Z4 M40i enough. Though a new one is a bit expensive with the desirable Handschalter Package – the only way we’d order it – pre-owned examples are a great way to get into a dedicated sports car platform at a decent price point. The convertible top, grippy sport seats, and driving experience all combine to make it one of the best ways to enjoy the B58 engine.
BMW M140i
It never came to the US unfortunately, but the M140i is a great fit for international shoppers. A curb weight of less than 3,500 pounds makes it plenty tossable. It’s rated at a lower output – around 340 horsepower – than most of the other models, but its still plenty nimble. Even better, you have a choice between 3-door and 5-door hatchback models.
While there are plenty of options when cross-shopping B58-powered crossovers, SUVs, coupes, and sedans, there are far fewer when it comes to the hatchback segment. It’s likely the last turbo-six-powered and rear-wheel-drive hatchback we’ll ever see, making it forever special. Which, of course, makes it a little more aggravating that we never got it here in the States.
BMW 640i xDrive Gran Turismo
I was selling cars when the 640i xDrive Gran Turismo came around, and at the time, we considered it one of the most heinous vehicles in the lineup. By today’s standards, however, I’d consider the 640i xDrive GT inoffensive at worst. It’s also the only way to get the B58 in a 6 Series.
While it’s unfortunate the beautiful Gran Coupe wasn’t ever offered with the B58, the GT is better for some buyers. It’s somewhere between an SUV and a wagon, which means generous passenger and cargo space. In fact, it offers more cargo space behind the rear seats than even the X3. Bigger and more luxurious than the 3 Series GT or 4 Series Gran Coupe, it’s super practical. And, thanks to the B58 engine under the hood, it’s pretty reliable and quick, too. Not a bad option on the used market – if you can find one.
