Low-production enthusiast cars always seem to be on life support. No matter how fast, refined, or just overall good they are (or how much pedigree they possess), relatively rare rides that prioritize fun over function always feel like they’re on the verge of leaving our shores or production lines altogether. In the case of the 2023 BMW Z4 M40i, this would be a great shame because it’s such an enjoyable choice in these driving-appliance times we’re currently living through.
The Z4 follows several generations of its own badge, the Z3 behind it, and the Z1 even further back, as the German brand's two-seater athletic drop-top of the past 30 years. There's a Z8 back there somewhere, too. This latest inline-six-powered G29-generation M40i is as at home on a twisty road as it is in a grocery store parking lot, and every form of easy, top-down cruising in between. Here's why it's a very fun convertible in all of the best ways.
|2023 BMW Z4 M40i Specs
|Base Price (as tested)
|3.0-liter turbocharged straight-six | 8-speed automatic | rear-wheel drive
|382 @ 5,800 to 6,500 rpm
|369 lb-ft @ 1,800 to 4,500 rpm
|9.9 cubic feet
|EPA Fuel Economy
|23 mpg city | 31 highway | 26 combined
|A spacious near-M convertible that absolutely rips.
This generation of BMW Z4 has been around since 2019 but underwent a mid-cycle refresh for this year's model. The car already looked great before, but slightly revised kidney grilles and other minuscule changes make it look just a smidge better. Especially when painted in my tester's optional San Francisco Red Metallic that's contrasted by the optional Shadowline Package’s black mirror caps and exterior trim. In light of BMW's current, extra-controversial styling elsewhere in its lineup, the Z4 is rather refreshing to look at.
Top up or down, it's a very handsome car with a classic sports car shape. I especially dig its wide rear hips; its long hood and short rear overhang make it seem like you're sitting on the rear differential—and you nearly are. It's dimensionally much larger than one might assume from looking at photos—a far cry from the simpler days of the E36/7 Z3. Cars are big these days, and the Z4 is no exception.
Inside, my tester's options made it a very pleasant place to be. With supple leather sport seats with good adjustment, power bolsters, and heating that came in quite clutch during an unseasonably blustery week. Stitched leather and Alcantara cover most surfaces, while any rubberized or hard plastic possesses a solid, quality feel. I wasn't keen on the amount of piano black trim that populates the center console and dash, but at least this Bimmer's iDrive controller helps cut down on fingerprints.
Driving the BMW Z4 M40i
The M40i is the most muscular BMW Z4 that we can get our hands on in the U.S. Because BMW is one of the most Lego-like manufacturers ever, everything underneath mirrors what you find in other 40i cars, like the M240i and M340i. Its heart is the venerable 3.0-liter B58 straight-six that produces 382 horsepower and 369 lb-ft of torque, which is sent to the rear wheels exclusively via an eight-speed ZF automatic gearbox and M Sport limited-slip differential.
BMW says that the 3,535-pound Z4 will reach 60 mph in 4.4 seconds and click off a mid-12 quarter mile time. It's an engine and drivetrain with true character, too, on top of frequently reminding me that it's seriously fast, regardless of traction or driving mode. Even just pulling away from a simple green light in Comfort mode, the angry B58 would rev up and briefly chirp the rear tires with three-quarters throttle before being reigned in by the ECU. Like when an excited big dog pulls hard on its leash and the owner has to really yank to bring it back in line.
It became a fun game to see what the Z4 would do on city streets with a sudden full jab of the throttle mid-corner—the rear tires would yelp and ever-so-slightly push the rear end out, but it'd quickly get right back into line. Again, like an excitable pitbull or rottweiler. Good job, BMW.
Bolted up behind its front 255/35/19 Continental summer tires is strut-type suspension, whereas its all fully independent multi-link equipment behind its rear 275/35/19s. Adaptive M Sport dampers give the Z4 a versatile ride, but even in Comfort mode, it errs on the side of communication and enthusiasm. People who are keen on the performance car life would call its ride quality perfectly acceptable, whereas folks who want optimum daily comfort might find it to be a bit too much. Especially if they regularly roll across Los Angeles County's no-man's-land-resembling tarmac.
The key to pure M40i enjoyment was in its settings. My custom M setting of choice happens to have everything as sporty as possible except for the engine. The Z4 might weigh over 3,500 pounds (though, that's actually pretty light compared to other modern Bimmers) and lack an actual roof, but it absolutely sailed through both wide-open sweepers as well as anything tight and technical with a lot of poise. BMW hit its mark with damper and chassis tuning, which is an improvement over what I recall about the pre-refresh version of this car. There was still plenty of cowl shake due to being a soft top, but it otherwise cornered incredibly flat at high speeds. Besides needing a little patience with the throttle on corner exit regardless of whether traction control was on, the Z4 is an immensely playful sports car.
Its steering in Sport mode exhibited excellent weight and was paired with a very nice, quick ratio. A decent amount of the road communicated its way to the wheel, though it was really just shockwaves of what the chassis transmitted rather than what the tires were feeling. My only real gripe with the Z4 M40i's steering and handling was that the entire front end felt a tad too vague and disconnected for my liking. Besides any aural cues, it was hard to tell what the front tires were experiencing.
When it came to stopping, the M40i's M Sport brakes were always up to the task, no matter how long I beat on them. Pedal feel was mildly firm and linear, with just a hint of grabbiness—smooth modulations were easy to quickly master.
All combined, the Z4 M40i rushed along with plenty of confidence and agility. It's impressive for its relatively large size, and even with traction control off, it felt quite planted and predictable.
The Highs and Lows
The Z4 M40i is a ravenous-yet-tame driving experience. It possesses plenty of thrills when you want, but will calm down and become quiet and comfortable for daily use. It's even quite spacious inside—my six-foot-three stature had plenty of leg- and headroom, and my noggin never crested the windshield's peak with the top down.
I mentioned earlier that my preferred custom drive mode has everything turned up to the max sans the engine. Reason being: The exhaust's loud pops and crackles got a bit old after a short while. They were a fun party trick at first, but I wish they were separately defeatable from the other adjustments that are also present in Sport mode, such as sharper throttle response and an overall more vivacious character. No matter the mode, the exhaust note was way too quiet when it wasn't burbling and crackling—I'd rather have a few more decibels over setting off car alarms and making passers play gunshots-or-fireworks.
Then, this Bimmer's iDrive 7 infotainment system was generally easy to operate but had a few annoyances. One was the SiriusXM screen quickly jumping to Apple CarPlay whenever I received a text interrupting my normal browsing. Then, having wireless CarPlay running while my iPhone 8 sat on the charging pad created a lot of heat—at one point, my phone refused to function normally until it cooled down a spell.
BMW Z4 Features, Options, and Competition
To hop in the most base Z4 trim, the 255-hp sDrive30i, it'll cost $53,795. This version will get you to 60 mph in the low-five-second range.
Moving up to this M40i trim with its far more potent 3.0-liter will cost at least $66,295. My tester's paint job and black Alcantara interior tacked on $1,900, the Driving Assistance Package added $700, another $950 gave it the Shadowline Package, and the Premium Package added remote engine start and parking assistant for $1,350. Its 19-inch wheels tacked on $600, then after a handful of smaller options, its out-the-door tag hit $73,620. If it were my money, I'd opt for the Shadowline package and ditch the rest; all of the fun-centric equipment like its M Sport brakes, adaptive dampers, and rear differential are all standard equipment on the M40i.
As far as what else is out there, there aren't a whole lot of options. For a pure drop-top-to-drop-top comparison, the Mazda MX-5 is far cheaper, but not nearly as spacious or fast. Though, it's arguably even more fun, so there’s that. The Toyota Supra is the Z's production line sibling and commands $45,735 and $54,695 for the 2.0- and 3.0-liter versions, respectively. The Porsche 718 Boxster is probably the Z4's most direct competitor and starts at $66,950, whereas packing a bigger 4.0-liter six-cylinder into the middle of its chassis starts at a cool $93,850. Finally, the Mercedes-AMG SL43 starts even higher at $110,950.
Value and Verdict
The 2023 BMW Z4 M40i is an absolute riot to drive. Its potent turbocharged inline-six packs so much torque and rips off the line with just-about-M-level brilliance. Being a convertible, it brings a sense of occasion to the act of tooling around town or pulling some respectable longitudinal and lateral g’s on your favorite twisty road. Its chassis is generally communicative, but the front end is unfortunately a bit too vague.
Despite that, though, it's a great all-rounder luxury convertible, and it's a shame you don't see more of them on the road. However, that might add a little to its appeal. It makes you stop and look when you see one cruise by, which can't be said for many other cars out there. In an era of homogenous design overflowing with crossovers and EVs, I'm glad BMW still makes this thing. And I hope it continues to do so.
Got a tip? Send it in to firstname.lastname@example.org