TEST DRIVE: BMW Z4 M40i — A Tough Audi TT RS Competitor

Roadsters are dead. Gone. Finished. Gone are the days when customers yearned for the wind in their hair exhaust noise filling their ears. Instead, the modern car buyer wants something sensible, efficient, high-tech and kind to the environment. In this new world of efficiency and sensibility, a two-seat, drop-top sports car just doesn’t make much sense. Which is a damn shame because this last generation of sporty roadsters is actually quite fantastic. The Audi TT RS is among those leading the charge to keep roadster around, though we know its eventual fate. However, there’s a new drop-top German that makes a good argument for keeping the segment alive, and one that gives the TT RS some real competition — BMW Z4 M40i.


There’s really only only one purpose for a roadster. Though sizes and shapes may vary, prices and luxuries may too, the only constant should be fun. And a fun roadster can be had in many different forms.


You have ultra expensive muscle car versions, like the Mercedes-AMG GT C Roadster. There are mid-engine, scalpel-sharp versions, like the Porsche Boxster. You even have simple, inexpensive and honest roadsters, like the Mazda MX-5. The Audi TT RS has its own unique personality as well, as it’s more of a turbocharged, all-wheel drive grip and speed monster. So roadsters come in all different flavors; varying in size, shape and price. But the essence of a proper roadster is the thrill it gives the driver. And the new BMW Z4 M40i is a surprising thrill.


Of all the different kinds of roadster on the market, the Z4 M40i is a bit of a mix, a greatest hits of sorts. It’s relatively small but still quite premium. It’s also traditionally front-engine and packs a big engine, making it a bit of a hot-rod. And while it’s high-tech under the skin, it’s a relatively simple car to drive. And, honestly, it’s the most fun I’ve had in a BMW in a very, very long time.


Powering the BMW Z4 M40i is a 3.0 liter turbocharged inline-six engine making 382 hp and 369 lb-ft of torque and I can honestly think of no better engine for it. In a car as small and light as the Z4, the B58 engine turns it into a hot-road. While it might look like a delicate sports car, something with proper European manners, it’s actually more of a muscle car than anything else and it’s absolutely hilarious.

All of its torque comes on like a sledgehammer, from low in the rev range all the way until its peak horsepower kicks in at the top half of the tach. From there, it keeps pulling and the BMW Z4 M40i can get from 0-60 mph in a claimed 3.9 seconds. I wouldn’t be surprised if it actually shave a couple of tenths off of that. While it might not have the outright character of the TT RS and its glorious 2.5 liter turbo-five, the BMW’s explosive power is extremely endearing.



Not only is it so explosive but it’s also wonderful to use. It’s so smooth you’d think it was running on clouds made from evaporated whipped cream. There’s an old adage for a smooth, yet powerful engine — an iron fist in a velvet glove — and it couldn’t be more accurate in describing the Z4’s B58.

But what makes Bavaria’s hot-rod engine even more special in the BMW Z4 M40i than in, say, an M340i, is the noise. More specifically, the fact that you can hear the noise without the nuisance of a roof interfering with it. With the top down, you can hear the engine’s full song and it sounds incredible. In my humble, and likely unwanted, opinion, the Z4 M40i is the best sounding BMW on sale. It’s deep and burbly at idle but it builds into a raspy, metallic crescendo and all of it can be heard sans roof. It’s just wonderful. Again, it’s not as soulful as the TT RS’s crazed five-pot but it makes a damn good noise.


Most importantly, it sounds good all the time. You don’t have to be in a certain mode, you don’t need to be near redline and you don’t have to be traveling at lose-your-license speed to enjoy it. It sounds great in all manners of driving and it makes even the most mundane of trips that much more interesting and exciting. Sure, sportier drive modes increase the noise but it even sounds great in its quiet, Comfort mode. Every opportunity to drive the BMW Z4 M40i is an event, something to look forward to. It will make you find excuses just to drive it.


While you won’t be disappointed when threading the Z4 M40i through some twisty roads, it’s not the sharpest tool in the segment. A Porsche Boxster is going to be the superior driver’s car and I’d even argue the Mazda MX-5 is, too. However, it’s just fun enough and I’d actually reckon it’s the better driver’s car than the Audi TT RS.


Though, one area where the Audi excels is grip. In anything other than dry weather, the TT RS will lunch the Z4 M40i thanks to its all-wheel drive nature. The Z4 is quite a tail-happy hooligan, which is fun but also a bit scary in wet weather. Admittedly, you don’t usually drive a convertible in rainy weather.


The Z4 steers with better precision than the TT RS, though. thanks to extremely aggressive front-end grip and a quick steering rack. But because the chassis is also well balanced and the back end likes to play, it will change directions very quickly, almost too quickly. It’s not hard to get its tail to step out but, thankfully, it’s easy to control and even to hold. If you want to try and be Chris Harris, the BMW Z4 M40i will make it relatively easy.


However, it’s not the most engaging car to drive quickly. The BMW Z4 M40i is not a momentum car, where you want to carry a ton of speed through corners and it’s not going to flow beautifully down a canyon road like a Porsche Boxster will. It’s just not that sort of car. That doesn’t mean it can’t be fun, though.


It’s fun in it’s own way, the Z4. Chuck it into a corner, get on the power early, get the back end a bit sideways, listen to its incredible engine and, once it straightens out, unleash all of its power and the Z4 M40i becomes a riot. It’s far more of a brash hooligan than a tidy sports car. If the Boxster is a scalpel, the BMW Z4 M40i is a machete. It might not be as precise but it’s just as fun.


I could talk to you about all of the practical bits of the Z4, such as the roof that can open and close in eleven seconds (or something similar, I never bothered to check) or how much its trunk can hold. However, none of that really matters.

One reason for that is because the fabric soft-top is basically just an emergency rain cover, in case it starts to pour while on already on the road. In any other weather, the top must be down. Even in the cold. There are few things in life as great as driving a fast, sporty roadster with the top down, in the cold, bundled in a good jacket with the heated seats and steering wheel on. Excellent.



The other reason is that practicality is irrelevant in the BMW Z4 M40i. It’s far too fun, far too exciting a car to care about how practical it is. Plus, the Z4 is a toy. It’s something to take out on the weekends to play with. It’s not a car that needs to be practical in any way, shape or form. So just sit back and enjoy the fun.


Of course, the BMW Z4 M40i isn’t perfect and there are probably better roadsters on the market. But the Z4 M40i is a hilariously fun car that’s faster than it should be, more exciting than you might expect and is completely and utterly unnecessary. It’s going to sell poorly because roadsters are dead and it’s probably not going to get a successor, as BMW will likely kill the Z4 model altogether, just as Audi will almost certainly kill off the TT Roadster. But it’s fun for the sake of being fun and for no other reason.



More than that, it’s the most fun I’ve had in a BMW in a long time and it’s one of the most fun cars I’ve driven all year. This new BMW Z4 M40i is a great roadster and is instantly one of the better ones on the market. If Audi intends to keep competing in this arena, it needs to be very worries about the new Z4.

Nico DeMattia

I've been in love with cars since I was a kid, specifically German cars. Now I get to drive them talk about them on the internet.