2007 BMW Z4 M Convertible

What's New for 2007

The BMW M Coupe and Roadster debuted as all-new models last year. As such, there are only a few minor changes for 2007, including a new standard tire-pressure monitoring system.

Introduction

For Hitchcock, dialing "M" meant murder. BMW has been known to dial M, as well. But in this case, any screaming you hear will be due to overloaded tires or passengers with wild eyes and death grips on the door handles.

As most automotive enthusiasts know, the letter M refers to BMW's subsidiary motorsport division. Through it, select BMW models are modified into serious performance machines and given distinct nomenclature. Though it has no number associated with it (as with the M3 or M5), the 2007 BMW M is, in fact, based on the Z4 sports car. In daily lexicon, it's usually referred to as the M Coupe or M Roadster, though some people also use "Z4M."

Currently in its second generation (a previous version was based on the old Z3), the M is much more than a mere dress-up kit or sport package. Much of its hardware comes from the now-discontinued M3. The car's high-revving 3.2-liter inline six-cylinder engine develops 330 horsepower and sends its power to the rear wheels through an exclusive six-speed manual transmission and a beefy limited-slip rear differential.

The M cars sport many other tweaks to the base Z4 as well, including a wider front track, a stronger rear subframe, hydraulic power steering for better feel (the Z4's is electric), 18-inch wheels and 225/45 front and 255/40 rear performance tires. The springs and dampers are sport-tuned, and the brakes are the same as those used for the old M3's Competition package. Even the stability control system has been altered to be less intrusive.

Yet what's really impressive about the 2007 BMW M Coupe and Roadster is that they go beyond the numbers. Of course, they're relatively lightweight (about a 3,200-pound base curb weight for the Coupe), have near-ideal weight distribution and can post blindingly quick acceleration times. But they also provide some of the best thrills you can get from a non-exotic sports car. Visceral and extreme, they bring out the driver's inner hooligan. Every departure from a stoplight is an opportunity to hit 8,000 rpm, every corner a chance to hang the tail out wide.

Though not the quickest BMW M product, this one is arguably the most driver-centric. With just two seats, a modest trunk and no automatic transmission, the M Coupe and Roadster come close to being road-going race cars. Yet this aggressiveness, so intoxicating at times, is also a failing. In all honesty, many of our editors prefer the Porsche Boxster S or Cayman S. The Porsche models are more expensive (sometimes by a lot), but they match the M's performance and, at the same time, are more polished in their moves and communicative in their purpose. And if one of these sports cars has to also serve as a daily driver, these are qualities that can't be ignored.

Body Styles, Trim Levels, and Options

The 2007 BMW M sports car is available as a hatchback coupe or a roadster with a power-operated fabric top. Special styling details, such as a more aggressive front fascia with larger air inlets, a pair of ridges in the hood and a set of quad exhaust outlets flanking a rear diffuser separate the M from its less potent Z4 brethren. Since the M is at the top of BMW's line, much of what's optional on the Z4 is standard. Standard fitments include 18-inch wheels, xenon HID headlights, leather sport seats and a 10-speaker audio system with a CD/MP3 player.

The optional Premium Package is pretty much a must. Not because it gives you auto-dimming mirrors, power seats (with driver memory), BMW Assist, Bluetooth connectivity and a premium audio system -- it does -- but because BMW sneakily makes this rather pricey package the only way to get cruise control. Other options include heated seats, a navigation system, wood interior trim and higher-grade interior leather.

Powertrains and Performance

The M has a 3.2-liter straight-6 engine that's rated for 330 hp at 7,900 rpm and 262 pound-feet of torque at 4,900 rpm. A six-speed manual gearbox is the sole transmission offering and a special limited-slip rear differential helps put the power to the pavement. In testing, we've found the M Coupe can hit 60 mph in 4.9 seconds. EPA fuel economy estimates are average for this class of car at 16 mpg city, 24 mpg highway.

Safety

The M comes with a stability control system, traction control, a tire-pressure monitor, rollover protection for the roadster and side airbags. Antilock disc brakes are also included, and they come with BMW's latest add-on features like automatic brake-disc drying. In NHTSA crash tests, the regular BMW Z4 Roadster earned four out of five stars for frontal-impact protection and a three-star rating for side-impact safety.

Interior Design and Special Features

The cockpit features a pair of aggressively bolstered sport seats, a chubby M edition steering wheel and a Motorsport-spec tachometer with a variable redline that settles at 8,000 rpm when the oil is fully warmed up. The speedometer reads to 180 mph, but the car's computer will cut you off at 155 mph. There's no iDrive available (thankfully, some would say) and the dash's knobs and buttons are exactly where you'd like them to be. The roadster's 9-cubic-foot trunk capacity remains almost unchanged when the top is lowered. The coupe, with its enclosed hatchback design, gives you a bit more space at 12.8 cubic feet.

Driving Impressions

Sitting in the 2007 BMW M feels like you're riding on the rear axle, and that's almost true. That long straight-6 engine under the bulging hood needs to be balanced somehow, and the driver's weight helps to contribute to the M Coupe's 50/50 weight distribution. The view down that elongated hood from what feels like the backseat is a bit old-school, and charming, too. There's no doubt this is a front-engine rear-driver.

Twist the key and the engine zings to life. It provides unrestrained gyrations up to the 8,000-rpm redline, along with a broad torque band that thrusts the car forward with the immediacy of a 1960s muscle car. Yet the M isn't for the casual driver. It feels like the Z4 the BMW engineers and test drivers originally intended to build before the focus groups electrified the steering, softened its edges and slowed its reflexes to make it less taxing to drive. The car's theme is immediacy: quick steering, instant brakes, direct throttle and caffeinated ride. The ride quality is actually harsh over broken pavement (particularly in the coupe), and keen senses are needed to keep the car tidy and in line when driven hard on canyon roads.