Eight Cylinders, Six Speeds, Four Doors
You can never really have too much of a good thing.
Just look at the 2008 BMW M3 Sedan. Introduced as a coupe only six months ago, now it has two more doors and added trunk space to boot. All this without any compromise in performance.
That's what we said to ourselves as the speedometer swung to an indicated 175 mph on the autobahn in Germany this week. And there was another 1,000 rpm to go on the tachometer before the rev limiter could be expected to kick in.
It's the Bavarian Motor Works
No matter how many doors the 2008 BMW M3 Sedan might have, an M3 always begins with its engine. The power of the DOHC 4.0-liter V8 in the 2008 BMW M3 Sedan is simply electrifying. It makes 414 horsepower at 8,300 rpm and 295 pound-feet of torque at 3,900 rpm.
Just as important, everything about this engine is an engineering marvel. It's a mix of aluminum alloys that weighs just 445 pounds (33 pounds less than the last M3's inline-6). Eight individual throttle butterflies for the cylinders combine with a very tall 12.0:1 compression ratio to deliver incredibly crisp throttle response, while the engine is capable of spinning its 44-pound crankshaft to 8,400 rpm, the highest rpm of any BMW production engine.
And believe us, the performance this 4.0-liter V8 gives to the M3 sedan is equally electrifying. BMW claims the 3,638-pound M3 sedan almost matches the M3 coupe in acceleration to 100 km/h (62 mph) with a 4.9-second run, just 0.1 second slower than the 3,573-pound two-door. The top speed is nominally limited to 155 mph, but some fiddling with the engine management system will let the speed swell appreciably. We saw an indicated 175 mph during one determined autobahn run.
This, of course, is not the first time the M3 has been given the sedan treatment. That distinction rests with the second-generation model produced in four-door guise from 1996-'98, which was a notable success in the U.S. As it happens, BMW did not follow it up in the third-generation M3 because of structural differences in front-end architecture between the E46 sedan and coupe.
The new M3 sedan is not the last of the models of the current M3, though. With the arrival of an M3 convertible just around the corner and talk of a wagon version later in the model cycle as well, there will be no shortage of M3s to tempt us.
Spot the M3 Sedan
As we've seen in the past, BMW's revered M division doesn't do things by half measures. This is fully reflected in the distinctive styling of the new M3 sedan. Rather than simply adopt the standard 3 Series sedan body for its latest model, it has concocted its very own unique version using the front-end styling treatment from the 3 Series coupe, including the kidney-shape grille, headlights, heavily contoured aluminum hood and boldly flared front fenders.
As a result, you get a car that mirrors the aggressive good looks of the M3 coupe right back to the A-pillars. From there on, though, the car receives the taller greenhouse, four doors and higher trunk of the familiar 3 Series sedan.
Added to this are all the usual M3 styling accoutrements, including a deep front fascia featuring sizable air ducts to feed the engine bay, a signature chrome vent in the front fenders, heavily chiseled rocker sills and an extended rear valance that incorporates an aero diffuser element and four prominent chromed tailpipes — all of which provide the M3 sedan with just the right touch of visual differentiation from the lesser 3 Series sedans.
The most notable clue to the exalted performance of this 3 Series sedan is its complement of visually arresting wheels and tires. These 18-inch cast-aluminum wheels feature 8.5-inch rims in front that carry 245/40R18 tires, while the 9.5-inch rear rims are fitted with 265/40R18 rubber.
Six Speeds Now, Seven Speeds Later
Still, you can forget the styling. The hardware that lies beneath is what really counts, because the M3 sedan's mechanical specification makes it virtually a carbon copy of the M3 coupe.
The centerpiece, of course, is M division's compelling new 4.0-liter V8. It is as sweet and soulful an engine as BMW has ever built, with linear, electriclike throttle response, big flexibility through the midrange and a wonderfully seamless delivery all the way up to its soaring redline.
The weak link, if it can be described in such a way, is the standard close-ratio six-speed manual gearbox. There is nothing intrinsically wrong with the action of the Getrag-built unit. The action is crisp and precise, although the throws are a little long to reduce shift effort and there's an awkward gate for 1st gear that requires a dogleg shift. Yet you can't help wondering whether this car would be quicker with an automated sequential gearbox.
And by this we don't mean the former M3's SMG transmission. BMW has just announced its new M double-clutch seven-speed transmission, which incorporates no fewer than 11 internal shift programs — five in automatic Drive mode and four in manual-shift Sport mode. This the first dual-clutch transmission designed to withstand engine speeds of up to 9,000 rpm, and BMW promises both utterly smooth shifts and an improvement in fuel efficiency.
The transmission is slated as an option for the M3 coupe, sedan and convertible. It makes each car 0.2 second quicker to 100 km/h (62 mph)
It's Actually Useful
Up to this point, we could well be talking about the M3 coupe. But the M3 sedan adds another dimension to prospective ownership that will undoubtedly make it a popular choice among those with real-world considerations: practicality.
While the coupe is capable of seating four in relative comfort, the sedan will take five at a pinch. Its rear doors also ease entry and exit to the rear, a crucial consideration for anyone who has ever fumbled with the three-point harness on a child seat (and in the dark, and maybe it's raining besides).
You can even bring more stuff along with you, as the M3 sedan affords 17.0 cubic feet of luggage capacity, although this is just a single cubic foot more than the M3 coupe.
There's a price to be paid in weight, yet the sedan is surprisingly only 55 pounds heavier than the coupe, tipping the scales at 3,638 pounds. Much of the weight increase comes from the decision to substitute a conventional roof for the coupe's carbon-fiber piece. The high cost of tooling just didn't seem warranted in light of smaller production numbers, BMW tells us.
The M Way of Driving
Not that any of this makes a whole lot of difference. On the road you can caress the M3 sedan through the controls just as you do the M3 coupe and it responds with the same deftness. There is beautiful weighting of the steering, brakes and clutch — all of which have been integrated electronically to work in delicious harmony. The driving position might be a touch higher and the windshield angle more upright, but the same responsive actions still greet the driver.
The sedan's rear-wheel-drive chassis has the same dimensions as the coupe, including the wheelbase, and it handles with similar poise and grips with similar ferocity. Its high-speed stability is staggering, allowing you to push up to big speeds with great confidence.
The nominal damping feels a little spongy given the level of performance on hand, but thanks to the adaptive nature of the dampers you can dial up a further two levels of stiffness. Leave it in Sport and you can't help but marvel at the tautness inherent in the body structure as you carve through corners at the sort of speed no four-door really has a right to.
Start looking for the handling limits and you discover there's a touch of understeer at the entry to corners, but we suspect it is only because the rear seems so well settled. BMW's remarkable M differential proportions torque to each rear wheel depending on the circumstances, and indeed the M3 is as complex as a Formula 1 car in the way the electronics adapt it for every change in driving style or road environment. In fact, you can dial it in for your own personal preferences with the MDrive control on the steering wheel.
The Line Starts Here
The 2008 BMW M3 Sedan is priced at $54,575, while the 2008 BMW M3 Coupe is priced higher at $57,275. Vehicles are scheduled to become available in March.
The M3 sedan allows you to go about your day-to-day business without having to give up the pure performance that is inherent in the M character. The M3 coupe might be slightly more focused, but it cannot provide the same level of practicality. As we said, you can never have too much of a good thing.
Edmunds attended a manufacturer-sponsored event, to which selected members of the press were invited, to facilitate this report.