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Enthusiasts shopping for a BMW X3 will assuredly be salivating over the ballistic X3 M models. Offered in 473- or 503-horsepower flavors, the Ms are capable hitting 60 miles per hour in the low-4-second range and are legit racetrack-capable machines. Problem is, a $70,000 base price isn't in the cards for everyone. What's slightly more palatable? How about the X3 M40i and its $55,000 starting price tag. It might not be as hot as the full-fledged M, but it isn't anything to write off, either.
Like the king-of-the-hill Ms, the X3 M40i is powered by a 3.0-liter, turbocharged inline-six engine. Its output checks in at a still-punchy 355 horsepower and 365 pound-feet of torque. All that peak twist is available for a long time between 1,520 rpm and 4,800 rpm, resulting in hard launches from stoplights and rapid midrange acceleration for easy expressway merging.
Sending power to all four of the X3's wheels is the fantastic ZF-sourced, eight-speed automatic transmission. It provides well-timed gear changes when left to its own devices, and a worthy manual shift function for a more involving experience behind the wheel. BMW claims the drivetrain allows the X3 M40i to scoot to 60 mph in 4.6 seconds, besting the Audi SQ5's 5.1-second and Mercedes-AMG GLC43's 4.7-second efforts.
If you can resist the urge to dip deep into the throttle to unleash all of the M40i's grunt, it'll return an EPA-estimated 20 miles per gallon in the city and 27 mpg on the highway. The latter figure I confirmed during a roundtrip run from Detroit to Cleveland, observing 26.5 mpg along the way.
The other part of the M40i equation is improved handling. Upping the 4,300-pound crossover's dynamics are a rear-biased all-wheel-drive system, adaptive M dampers and bigger M Sport brakes with four-piston front calipers. On my test car, optional 21-inch split-spoke wheels wrapped with Bridgestone Alenza tires also help matters quite a bit.
All of this better-handling equipment works together to create a luxury crossover that rips through corners with loads of composure and grip. When the car is in Sport mode, the steering is nicely weighted and responsive to inputs and helps the X3 change direction in a brisk manner. As for the brake upgrades, they expertly kill speed in a hurry, enabling you to dive deeper into braking zones. No, the M40i isn't as hard-core and track-focused as the Ms, but it's plenty capable of providing backroad thrills on the way home from work.
Do the M40i's tighter reflexes mean compromises in ride quality? Surprisingly, not really, which surprised me, especially considering the bigger wheels and lower-profile tires. Bump stiffness may be a tad firmer, but with Comfort mode engaged the suspension softens the blow from road hazards for a more-than-acceptable daily ride quality.
Compared with the base X3, the M40i wears more aggressive fascias, with larger air dams up front, body-color side sills and high-gloss black roof rails. Throw in the aforementioned split-spoke wheels and the M40i does sets itself apart from its less-potent brethren quite a bit.
Anyone expecting drastic changes inside of the M40i will be disappointed. Outside of more supportive sport seats, a thick-rimmed M steering wheel and some M logos here and there, it's a typical BMW cabin. That means surroundings are cleanly styled, controls are intuitively laid out, materials are of acceptable quality and there's a serviceable amount of room for people riding in front and back. There's also quite a bit of cargo room on offer, with 28.7 cubic feet in the trunk area that grows to 62.7 cubic feet with the rear seats put down.
On the technology front, a well-sorted iDrive 6 system quarterbacks infotainment functions with an 10.2-inch touchscreen and center console-mounted controller. Both control options are simple to use and responsive while working through the onboard navigation, 16-speaker Harman Kardon surround-sound stereo, Wi-Fi hotspot, Bluetooth and Apple CarPlay. Frustratingly, BMWs still don't support Android Auto.
Not missing from the X3 are numerous ways to juice up phones and other smart devices. Up front, customers can install an optional a wireless charging pad, in addition to having easy access to USB ports and a 12-volt outlet. For folks riding in back, there's another 12-volter located on the back of the center console.
Kicking up the X3's safety story a notch are standard forward collision warning with automatic emergency braking and front and rear parking sensors, while a gaggle of other active safety features are available. Adaptive cruise control, blind-spot monitoring, lane departure warning with lane-keep assist, a 360-degree camera and a head-up display (HUD) can all be had for an extra cost.
Unlike my $68,520 test car that's done up with options galore, I'd adopt a more conservative approach to building my ideal BMW X3 M40i. With the $54,650 base car (not including $995 for destination) as a starting point, I'd begin with a $550 glacier silver metallic paint job just like the car pictured here. From there I'll add the $700 adaptive M suspension to have the ability to enjoy flatter cornering or a more forgiving ride at the push of a button. The $3,050 Premium Package is a must, mostly for the heated front seats and steering wheel that'll help make winter bearable, and a $500 Driving Assistance Package is another must-have in order to get blind-spot monitoring. Finally, I'll throw in the $500 wireless charge pad and spoil my ears with the $875 Harman Kardon audio setup, bringing my ideal X3 M40i's sticker to $61,820. Not too bad.
I know the idea of having the baddest BMW X3 in the land remains the ideal scenario for performance car junkies because they want the most horsepower and tightest handling. And if your bank account allows for it, then by all means, go nuts and buy yourself an X3 M.
But if the M is a little too rich for your blood, then the M40i is far from a terrible consolation prize. It's still darn quick in a straight line, highly capable through bends and compliant for normal slogs when it needs to be. And there's definitely no shame in any of that.