You don’t want to mess with a good thing, so Mercedes didn’t change too much about its 2007 Mercedes Benz SL550 roadster. Underneath the hood, a new 5.5-liter V-8 engine matched to a seven-speed automatic transmission compelled the name change from SL500 to SL550, although outsideNorth America, the name will remain SL500.

The new engine produces 382 hp from those 5.5 liters, up 80 hp from the previous engine. Torque also gets a boost, moving up 52 lb-ft to 391. As you’d expect, this is a thoroughly modern and sophisticated chain-driven, double-overhead-cam engine with variable-valve timing to get the best balance between performance and efficiency.

Hooked to this engine is a new adaptive seven-speed automatic transmission called the 7G-Tronic, which comes with a sports system that includes paddle shifting on the steering wheel. It shifts smoother, but engineers say the shifts are also 30 percent faster.

The second generation of Mercedes’ Active Body Control is installed to the SL550. It allows 60 percent more control of the suspension, to keep the car flat when the driving gets strenuous. The entire active suspension system and various brake assists work together to - well, they can’t change the laws of physics, but they do extend the time until they take effect. The result is to make every driver better and safer without their even realizing it.

The appearance changes are subtle. A new front air dam, front grille, revised taillamps and redesigned door-entry sills, and a new 18-inch ten-spoke wheel are the extent of outside updates. Inside, the upgrades are the materials - new high-quality leather and some new colors, including black and red, and some new toys-and-trinkets like Sirius Satellite radio and hands-free telephone capability (you have to buy the Bluetooth or Multi Handset Interface separately).

To honor the 50th anniversary of the most famous of this line, the 300SL, the North American market will get an SL Roadster 50th Anniversary Edition. Just 550 of them will be sold, and they’ll feature exclusive double five-spoke wheels, a brown leather and black ash trim interior, and a pewter-colored exterior.

Prices won’t be released until closer to the April sale date, but expect the new SL550 it to go up about a percent or so. -David Schmidt

This entry was posted on Sunday, February 26th, 2006 at 11:02 am and is filed under Auto Show [t], Car Models [t]. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.