German Car Zone

Merc1 · 02-13-2008, 01:27 AM

The gray line represents the steering ratio range on '08 SLKs, while the blue line shows the range on 2009 models with direct-steer.

Mercedes engineers compressed the gear teeth in the center of the steering rack to achieve a broader ratio range for the '09 SLK.

On Vacation With the Germans

Even the 2009 Mercedes-Benz SLK55 AMG roadster can get lost on the Côte d' Azur, a strip of coastal bliss that runs along the Mediterranean from Saint Tropez, France, to Ventimiglia, Italy, passing through the Principality of Monaco. Beauty and wealth are in such voluptuous quantities here that everyone takes it for granted. Unless you're Prince Albert II, you won't attract any more attention in this open-top AMG-modified Benz than you would in a rusty Fiat Panda.

Yet anonymity doesn't spoil the fun of driving the SLK55. If anything, it enhances the experience. You feel like you're getting away with something.

Nobody else feels the gratuitous rush of torque from the 5.4-liter V8 that gathers itself together right off idle. Nobody else knows the deep exhaust note that knots itself around the open cockpit, muting distractions like the rush of the wind, the calls of mating gulls or (even worse) a talkative passenger. Nobody else picks up on the indelicate belch of the 355-horsepower V8 when you lift off the throttle.

It borders on crude to speak this way about such a pretty little hardtop convertible, but the 2009 Mercedes SLK55 can be a wonderfully nasty weapon on the back roads of southern France — and it's yours alone to enjoy.

Freshened for Your Pleasure (Sort of)

Since 2009 marks a midcycle mechanical refreshment for the SLK-Class, you might be surprised we're writing about the SLK55 instead of an all-new SLK63. But this is a small car with a wheelbase 13 inches shorter than the C-Class sedan, so packaging the 6.2-liter AMG V8 would likely be neither physically tidy nor cost-effective.

As such, a normally aspirated 5.4-liter V8 is still the source of motivation for the speediest SLK. The V8 is still rated at 355 hp at 5,750 rpm and 376 pound-feet of torque at 4,000 rpm, and a seven-speed automatic transmission continues to drive the rear wheels.

Nor did the AMG division make any changes to the suspension, brakes or tires. Really, the only update that affects the driving experience is the adoption of the new Mercedes-Benz "direct-steer" system, which is also standard on the lesser SLK350 and SLK300 (formerly the SLK280).

"Direct-steer" is Benz terminology for variable-ratio steering, but this isn't one of the fancy, computer-actuated systems that abruptly switches ratios when it senses that you're taking big cuts at the steering wheel. Instead, this setup does its work in more subtle fashion based on variation in shape, angle and spacing of the gear teeth on the steering rack.

In actuality, the 2005-'08 SLK already had a steering rack with different-size gaps between the gear teeth, yielding a ratio that varied between 16.9:1 on-center and 11.9:1 at full lock. The major difference for the 2009 model is that the teeth are more compressed in the center of the rack, so the ratio range now spans from 15.9:1 to 9.2:1. The most dramatic quickening comes at 100 degrees off-center: Before the ratio was 15.3:1 at this point; now it's 11.9:1. In addition, direct-steer reduces the distance from lock to lock — just 2.0 turns of the wheel compared to 2.75 for the 2008 model.

On the aesthetic side, the 2009 Mercedes-Benz SLK55 AMG has the shorter nose, larger outside mirrors and tidier tail of other '09 SLKs. But to our disappointment, it still has a blacked-out lower front fascia instead of the racy new Formula 1-inspired split. Head on, it looks less virile than the four-cylinder SLK200 that Europeans will be driving.

Good thing you can't see this from the cockpit.

A German on Vacation in France

Germans love to spend their holidays on the Mediterranean, and after a few minutes behind the wheel of the Mercedes SLK55 AMG, you realize they've purpose-built this car for driving in the south of France.

The streets are crowded and narrow here, but the slender SLK feels no more cumbersome than a subcompact. Our AMG model's brakes are strong and easily modulated, and you quickly appreciate them because many intersections aren't even posted with signs, much less controlled by traffic lights (and pedestrians tend to cross against the lights at the ones that are).

If you want to cut loose, there are many excellent roads nearby in the foothills of the Maritime Alps. It's a little colder up here, but as long as the sun's out, there's no need to raise the SLK55's retractable hardtop. Wind management is close to perfect in this convertible.

Tight, decreasing-radius turns are common on the climb to Col de Brouis. With a big V8 up front, this hardtop convertible can't attack them with the precision of a Porsche Boxster. If you like a little power-on oversteer with your corners, however, it's available, controllable and always entertaining.

The variable-ratio steering feels quick as you set up for these turns, but the transition is linear and never seems unnatural. We wouldn't mind more feedback, but this has never been a strong suit of the SLK and we didn't expect a midcycle model refreshment to change this.

Falling Short of Perfection

Between corners, the SLK55 feels like it supports the claim by Mercedes that it will get to 60 mph in just 4.9 seconds, and it quickly overtakes delivery trucks and aged Citroën Saxos. We're not getting throttle blips on downshifts, however, even when we request them via the left-hand shift paddle. Evidently, this visceral pleasure is unique to the SLK350's engine-management software, as the V8's torque output puts too much strain on the hardware. At least the AMG-tuned transmission makes good on the promise made by its "Speedshift" name when you're going up through the gears.

Ride quality is a bigger concern about the 2009 Mercedes-Benz SLK55. Our test car had the optional AMG Performance Package, which incorporates spring and damper ratings that are 20 percent stiffer than the standard setup. Although the SLK55 affords quite good body control on mountain roads, the trade-off in comfort borders on impractical. Unless you're planning to modify your SLK55 into some sort of strange and extravagant track-day car, you'll find the ride too harsh.

The AMG model also features a different brake package, with 14-inch front rotors and six-piston calipers in front (instead of 13.6-inch rotors with four-piston calipers), and 13.0-inch rear discs with four-piston calipers (instead of 11.8-inch rotors with two-piston calipers). You'll also find carbon-fiber interior trim and an elevated speed limiter of 174 mph.

The AMG Indulgence

Mercedes hasn't yet released pricing for the 2009 SLK55 AMG, but the company says it shouldn't stray far from the '08 model's $64,025 MSRP (including destination) when it goes on sale in May 2008. That's big money, yet there's something enticing about a car that looks like a feminine boulevard cruiser but wags its tail like a muscle car.

You really do have to want such an unusual combination, though, because the SLK350 with its 305-hp V6 comes so close to the SLK55 in performance and attitude. Even if you figure in a slight price increase, the SLK350 should still cost more than $10,000 less than the AMG roadster. And the SLK350 is capable of hitting 60 mph in 5.3 seconds, Mercedes tells us, and to our ears its exhaust note is nearly as butch as the SLK55's.

There's no point trying to justify the 2009 Mercedes-Benz SLK55 AMG with your calculator. Instead, you have to think of it like a vacation on the Côte d' Azur. Expensive and perhaps frivolous, yet unforgettable.

2009 Mercedes-Benz SLK55 AMG First Drive

M

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German Car Zone

Edmunds Inside Line - First Drive: 2009 Mercedes-Benz SLK55 AMG