Comparison Test: 2007 BMW 335i vs. 2008 Mercedes-Benz C350 Sport

BMW and Mercedes-Benz are separated by about 150 miles and a rivalry as fierce as the one between Coke and Pepsi.

BMW builds the 2007 335i Sedan in the Bavarian city of Munich, while Mercedes-Benz has just released the all-new 2008 C350 Sport from its headquarters in the Swabian city of Stuttgart. Though Mercedes has long had the upper hand in terms of both stature and commercial success in Europe, the BMW 3 Series outsells the Mercedes-Benz C-Class by more than a 2-to-1 margin in the U.S., some 120,180 to 50,187 last year.

It's a rivalry that even carries over into competition on the racetrack, where BMW and Mercedes-Benz have a long history of competition in the German Touring Car Masters (Deutsche Tourenwagen Masters or DTM), which is as close to NASCAR as you can find in Germany, and are presently locked in battle for prestige in Formula 1.

So when you compare these cars, it's about pride, not just money. And now that there's an all-new generation of both the 3 Series and the C-Class, the battle begins again. Which would you bet on, the player from München (which translates as "monastery"), or the one from Stuttgart (which translates as "stud farm")?

The Players
Available this August, the W204 C-Class has an ultra-rigid unibody, improved steering, lightweight suspension components integrated with adaptive dampers, and world-class safety systems. This restyled sedan now has more passenger volume and more interior features, plus a multimedia information and entertainment system that sets a new standard in the class.

We secured the sportiest version of the 2008 C-Class, the C350 Sport with its 90-degree, DOHC 3.5-liter V6, which puts out 268 horsepower. Its base price is $37,275.

The E90 model of the BMW 3 Series arrived for the 2006 model year, and it predictably represented another move upward in size and sophistication. The most controversial aspect of the new car is its top-of-the-line twin-turbo 3.0-liter inline-6, the first in what is expected to be a full range of BMW turbocharged engines.

We obtained the sportiest version of the 3 Series, a 2007 335i Sedan with a twin-turbocharged, 300-hp 3.0-liter inline-6. Its base price is $39,675.

We're acutely aware of the price and horsepower discrepancies between these two sedans. In precise terms, it's a difference of 32 hp and $2,400, so the BMW makes you pay about $75 for every additional horsepower it offers. We might have chosen the $33,175 BMW 328i sedan with its normally aspirated, 230-hp inline-6 for this comparison against the C350, but these cars don't line up very well.

What we have here is the best possible edition of both the 3 Series and the C-Class, the cars that best express what each manufacturer is hoping to accomplish in this category. We're asking these cars to compete on the merits of performance, top-dog 3 Series versus top-dog C-Class.

It's All About Power
Let's get the numbers out of the way. In a sprint, the 300-hp BMW outpaces the 268-hp Mercedes by 1.2 seconds to 60 mph and 0.9 second in the quarter-mile. The true display of the BMW's horsepower advantage, however, lies in its trap speed at the end of 1,320 feet, and the 335i has a 6.5-mph advantage. Each car has an automatic transmission (a six-speed in the BMW and a seven-speed in the Mercedes) that upshifts with the crispness and sophistication you'd expect, and each offers Drive, Sport and Manual modes. The BMW's automatic is set apart by shift paddles incorporated into the steering wheel, a $100 option that delivers quick, matched-rev downshifts — cool, affordable and worth it.

To quote our logbook after the turbocharged 335i's run, "Launching is a bog or boil affair. Too much throttle and the tires will spin wildly in 1st gear; too little and it will leave slowly, off boost." Meanwhile, the C350's logbook notes, "Best launch was with the traction control shut off, but without brake torque or wheelspin." The 3 Series has power, but the C-Class has traction.

Make It Stop, Make It Stop
Hammering the brake pedal from 60 mph again showed the BMW to be the more capable car. Both cars are equipped with four-wheel discs and ABS with electronic brakeforce distribution, brake assist, brake drying and hill-start assist — some of these features are new to the C-Class for 2008. All four discs on the BMW, however, are larger in diameter than those of the C-Class. The test results reveal one excellent stop from the C350 at 118 feet, and one outstanding stop from the BMW 335i of just 112 feet.

The brakes of both cars proved utterly free of fade, even during our tortuous canyon runs through Malibu. When it came to city driving, though, the BMW's brakes exhibited an odd, sticky, on-off behavior below 5 mph that sometimes made it difficult to come to a halt smoothly. On the other hand, the Mercedes' brake pedal has a little too much stroke built into its action.

Round and Round We Go
It's interesting to discover that these two sedans with optional sport packages now share wheelbase dimension (108.7 inches), matching tire sizes (front, 225/40R18; rear, 255/35R18) and even rear-wheel track width (59.6 inches). The as-tested weights show the 3,592-pound C350 to have a weight distribution of 53 percent front/43 percent rear, while the 3,641-pound 335i offers 50 percent front/50 percent rear weight distribution.

The C350 dances far more adeptly than it has before, but it simply cannot match the practiced footwork of the 335i. On the skid pad, the best combined laps show that the BMW's run-flat tires deliver a sports-carlike 0.88g performance, and the C350 can muster only 0.83g. A similar story plays out in the slalom, where the BMW snakes through the cone course at 69.2 mph compared to the Mercedes at 67.6 mph.

Our testing logbook says, "Both the balance and the grip of the C350 are trustworthy and it's easy to find the limits. While there's certainly more information coming from the steering than in the previous C-Class, this is by no means a class leader in terms of feel. Good, just not great." Next to the BMW's name, the logbook notes, "It might not be the quickest in its class through the slalom, but it feels the best in class with its intuitive steering and brilliant transitional response."

A Ride Through the Real World
Highways seem a little smoother in the C350 than in the 335i, yet the world is also a little quieter in the BMW because the larger outside rearview mirrors of the Mercedes produce more wind noise. The BMW's ride is a little busier, though not punishing thanks to its optional Sport suspension and standard run-flat tires. Rough patches are acknowledged, but disruptive events dissipate rapidly and never linger.

The C350's new adaptive shock absorbers are meant to offer lots of compliance in the first centimeter of travel, and they do. Most of the time, the C-Class delivers what almost everyone would describe as a more comfortable ride, although we noted the C350 did transmit more tire noise over rough pavement than the 335i. This might be due to the differences between the Continental ContiSport Contact3 tires of the Mercedes and the Bridgestone Potenza RE050A tires of the BMW.

Room With a View
The Mercedes-Benz is all business, with its black, tone-on-tone interior treatment enlivened by chrome and aluminum details. The silver instrument panel surround is specific to the Sport, as is the black bird's eye maple trim. It's a luxurious look.

The BMW is visually interesting, with organic curves. The small buttons are more inscrutable than those in the Mercedes, and they seem to be part of an overall design theme rather than necessary interfaces for the driver.

The C350's standard eight-way power seats feel ultrafirm at first, but we found them very supportive for a long-haul drive. Even so, we thought a Sport-designated model should offer more lateral support, even if just for the driver. Ten seconds in the driver seat of the 335i make you admire a design that somehow manages to combine a supportive profile with long-distance comfort. You have to keep in mind that these seats are part of the 335i's $1,700 Sport package, though.

There's enough space behind the wheel for almost every driver, but headroom is 1.5 inches less in the C-Class because of the sunroof that is standard equipment. As far as the rear seat goes, the measurements suggest the 3 Series has a slight edge. Yet it's useful to remember that these are not midsize sedans, and limousine comfort is not part of the package.

The Electronic Connection
Thanks to the use of hardware and software from other Mercedes-Benz models higher up the chain, the C-Class now comes standard with a clever 5-inch pop-up screen on the dashboard, nicely done controller on the center console and intuitive software to connect the two. While we must give credit to BMW for pioneering the console-decluttering trail with iDrive, there have been vast improvements and innovations since this technology was introduced by the 2002 BMW 7 Series.

The C-Class' Multimedia package, a $2,700 option, brings together all of the car's entertainment, navigational and system settings in a highly logical manner. This world-class system includes a navigation system based on a 30GB hard drive that affords 4GB of music storage (about 1,000 songs ripped from a CD or memory card), an in-dash six-disc CD/DVD-Video/DVD-Audio changer, 450-watt Harman Kardon Logic 7 surround-sound audio with voice-control functions, and the option of an upgraded 7-inch high-definition screen. Even Sirius Satellite Radio is standard equipment. Nothing in BMW's entire options list comes close to what you can buy for any 2008 C-Class.

It's Not Always About the Numbers
When a car as good as the 2008 Mercedes-Benz C350 comes along, it'd be nice to suspend the rules of engagement for awhile. The C350 falls short only because it's matched with competition as tough as the 335i.

We wholeheartedly endorse the C-Class. Rather than try to out-BMW a BMW, Mercedes-Benz has chosen to fortify its best-selling model line with a chic exterior and outstanding standard and incomparable optional equipment. Even the price makes sense when you consider a C300 with a six-speed manual transmission starts at $31,975.

But it boils down to this: The 2007 BMW 335i provides an unrivaled driving experience. Its defining feature is its twin-turbo inline-6, an engine that rewards the horsepower fiend in all of us. In addition, the 335i carves up the road with a chassis that always assures you that there's plenty of car under you no matter how fast you drive.

In contrast, the 2008 Mercedes-Benz C350 Sport rewards a driver who is less interested in absolute performance than a simple degree of driving exhilaration, and who enjoys style and infotainment technology usually reserved for more expensive models in the Mercedes portfolio.

Even as these cars have grown closer in size and performance, they still go about their business in ways that are as different as Coke and Pepsi, Munich and Stuttgart.

The manufacturers provided Edmunds these vehicles for the purposes of evaluation.