The Good: A powerful V-8 engine and a smart seven-speed automatic transmission make up the 2009 Mercedes-Benz C63 AMG's power train. High points in the cabin electronics include excellent sound from a Harmon Kardon stereo, hard-drive music storage, and a full-featured Bluetooth phone system. The Bad: Gas mileage isn't going to be good with a 6.2-liter engine. The navigation system doesn't offer traffic or weather, which are features that are starting to be incorporated in other cars. The Bottom Line: The 2009 Mercedes-Benz C63 AMG combines very impressive performance on road and track with first-rate cabin electronics, making it fun and convenient. Just make sure you budget for gas. Photo gallery:2009 Mercedes-Benz C63 AMGMercedes-Benz's smallest U.S. sedan, the C-class, continues to impress us, this time with the sport-tuned 2009 Mercedes-Benz C63 AMG version. We previously reviewed the C300, and found that its updated electronics put to shame the tech in more expensive models from Mercedes-Benz. With the AMG version we have a car that competes with the BMW M3, not only in cabin tech but also in sheer performance and the exhilarating drive it offers. The cabin electronics in the C63 are the same as in the C300, with the latest version of Mercedes-Benz's navigation and phone system. The sound produced by the audio system blew us away, as did the sound from the engine. The C63 gets the same 6.2-liter AMG engine it uses in the much bigger S63, resulting in better power-to-weight. The car's shorter length and sport-tuned suspension result in nimble handling. Test the tech: Sound off The C63 AMG's engine produced a vicious bark when fired up, the kind of sound that sends small dogs running, makes any ninjas in the vicinity go into a fighting crouch, and puts even the most macho gearheads into a swoon. At the same time, our ears were delighted by the silky purr of an Italian in our garage. We decided to enlist Wayne Cunningham, Antuan Goodwin, and Mike Markovich as judges to determine which had the best engine sound, the Mercedes-Benz C63 AMG or the Maserati GranTurismo. Our judges gathered around each car and listened to the engine note as we turned on the ignition, then revved it up. Because the Mercedes-Benz limited the revs to 4,000 in Neutral and Park, we set that as the upper limit for both cars. The C63's 6.2-liter V-8 is a work of art, hand-built by an AMG engineer.The GranTurismo was first up. It uses a 4.2-liter V-8 with variable valve timing and four valves per cylinder, producing 405 horsepower at 7,100rpm and 339 foot-pounds of torque at 4,750rpm. Its redline is 7,500rpm. The engine started with a little cough, and then whirred as the revs built up. We built up engine speed to 4,000rpm, let it drop, then revved it up again. Markovich said of the GranTurismo's engine, "It doesn't have that sort of rasp I would expect from an Italian engine; more refined, befitting the character of the car." Goodwin agreed that it was a refined sound, and he had expected it to be more high-pitched. Cunningham felt that it wasn't quite like a Ferrari's engine sound, but it seemed to benefit from Italian tuning, eschewing harshness for a fine, silky rumble. Next up was the 2009 Mercedes-Benz C63 AMG, the tuned-up version of the C-class, featuring a 6.2-liter V-8, also with four valves per cylinder and variable valve timing. This engine produces 451 horsepower at 6,800rpm, with a 7,200rpm redline, and 443 foot-pounds of torque at 5,000rpm. The C63 started with an immediate bark, and was overall louder, as we would expect from the increased displacement. Cunningham noted the staccato quality of the sound, that you can "hear the valves and injectors working." Goodwin appreciated the immediate roar from the engine at the start. "The C63 sounds harsher than the GranTurismo," Markovich said, "but it's putting out a lot more power." Our judges give a good listen to the C63's engine. Our judges also admired the look of the engines, although they noted that most of the GranTurismo's engine is hidden by black plastic cladding, with just a nice Maserati trident badge on the intake manifold. The C63's engine is more exposed, with a gray crackle finish on the intake manifold and a small plaque with the signature of the engine builder. In the final assessment, the judges favored the sound from the C63. The GranTurismo didn't stand out enough, with its more refined and muted song. As Goodwin pointed out, "As a sports car guy, I like the C63 better. It sounds like its going to beat you up and take your lunch money." To hear the engine noise and our judges, listen to episode 79 of Car Tech podcast. In the cabin In the cabin, the flat-bottom steering wheel and AMG logo on the instrument cluster let you know this is the sport-tuned version of the C-class. The prominent side-bolstering on the seats is also a good clue. But the rest of the gear is standard for the C-class, with a mostly black interior accented by silver trim here and there. No two-tone fanciness for the sporty C63. The car gets the Mercedes-Benz Command interface, which mostly consists of a knob\/button\/joystick on the console augmented by back and clear buttons. This minimal switchgear does a good job of letting you access all the car's functions, including navigation, stereo, and cell phone system. You also get a set of quick access buttons for navigation, stereo, and phone on the instrument panel, along with a keypad. The Command controller is fairly simple, but works well with the car's software interface.The navigation system stores its map data on an in-dash hard drive, allowing much more data than a DVD-based system and extra space for music storage in something Mercedes-Benz calls the Music Register. The maps are high resolution and street names have white outlines around black lettering, making them very readable. We were impressed by how quickly it calculated and recalculated routes, and we also liked its route guidance graphics, which even gives lane guidance on freeways. Destination entry is fairly easy using voice command or the Command interface. Lacking are advanced features such as traffic or text-to-speech. Unlike other hard-drive-based navigation systems that offer almost 10GB of music storage, such as the one in the Infiniti M45x, the C63's system only offers 4GB. But that's still a substantial amount of music, equivalent to modern flash-based MP3 players. When you insert a CD into the drive, you have the option of ripping it to the hard drive, and the tracks will be automatically tagged with appropriate song, artist, and album names from a Gracenote database. The car also has iPod integration, although the system in our car didn't seem to work properly. It wouldn't show the iPod interface on the main LCD, merely letting us skip through songs on the instrument cluster display. We believe this fault was because of our C63 being a preproduction car, as we had seen good iPod integration on the C300. The C63's six-disc changer also reads MP3 CDs, and we had Sirius satellite radio. The Gracenote database recognized the CD, and will add appropriate ID3 tags as the system rips tracks to the car's hard drive.The Harmon Kardon audio system in the C63 sounded amazingly good. Listening to some lossless music from our connected iPod, we were blown away with the separation and clarity. We've heard some amazing systems recently in the Jaguar XF and the Audi A8, and this system in the C63 competed well. There were moments when the system had us looking at where we had heard a particular instrument in the cabin. The audio system is composed of 12 speakers, including a center and a subwoofer, powered by a 320-watt 8-channel amplifier. The 320 watts may not seem like much, but this system uses it well. The phone system in the C63 is also quite good. We had no problem pairing it with a Samsung phone, although we did hit a glitch with getting our contacts into the car. This failure seemed more to do with the individual phone model we were using, as the car's phone system can import contacts, letting you access phone numbers by name. Under the hood All of the cabin electronics are the same as you would find in the C300. The real reason for the 2009 Mercedes-Benz C63 AMG is its performance tuning, which makes it an incredible car to drive. Fitting yourself into the bolstered driver's seat only begins to let you know what the C63 can do. Hit the start button and hear the heavy bark of the engine, and you're getting closer. But it's when you put the shifter into Sport mode and put the hammer down that the C63 reveals its true character. It will pin you to the seat, yet remain planted as you guide it through the turns. What moves the C63 forward is that hand-built 6.2-liter V-8, adorned with a plaque inscribed with the name of the engineer responsible for its assembly. The engine is made from a silicon-aluminum alloy and a new type of coating in the cylinders that decreases friction, according to Mercedes-Benz, which also claims a 4.3-second 0 to 60 mph time. There are two ridges in the hood, the one in front of the driver making a perfect gun-sight to aim down the road. This engine is mated to a seven-speed automatic transmission, what Mercedes-Benz calls the AMG Speedshift Plus. Gearheads may fault Mercedes-Benz for not offering a manual or a double-clutch transmission, but the company has done a good job of tuning the automatic for performance. We got a chance to test the C63 AMG on the track at Laguna Seca raceway earlier this year, and found that, in sport mode, the transmission anticipated our needs well. As we braked on the approach to a turn, it quickly downshifted, holding the lower gear as we accelerated out of the turn and up the following straight-away. It only upshifted when we built up speed and kept the wheels straight. The transmission also has a manual mode, where you can select gears using the shifter or paddles mounted to the steering wheel. According to Mercedes-Benz, in sport mode it shifts 30 percent faster than in drive, while manual shifts happen 50 percent faster. You can get the back to swing out a little bit in the corners, but it's not as ready to let loose as the BMW M3. In our testing, we found that the C63 pivoted nicely in hard corners, although we did have a moment where the traction control intruded heavily. This behavior was because of the car's Electronic Stability Program being in its normal mode. You can set the EPS to a sport mode by briefly hitting the ESP button, which will let the back come out more than in standard mode, similar to the M3's programming. We had the opportunity to drive a different C63 AMG on the track at Laguna Seca, seen here going through the corkscrew.The car's suspension is substantially different than the tamer C300, sporting a 1.4-inch wider front wheel track. The sport-tuned suspension delivers a stiffer ride, but we found it reasonable under normal driving conditions. EPA mileage numbers haven't been published for the 2009 C63 AMG as of this review, but don't expect them to be good. In our testing involving a combination of freeway, city, and winding mountain roads, we averaged 16.2 mpg. Likewise, emissions ratings haven't been published, but we expect it to meet California's minimal LEV II rating. In sum The 2009 Mercedes-Benz C63 AMG goes for a base price of $55,975. We don't have option pricing at this time, but we expect, as in other AMG models, the Harmon Kardon audio system and the navigation system are standard. That price makes it less than a fully-loaded BMW M3, its main competitor. We found the driving character of the C63 AMG every bit as good as the M3, and the cars equal out in electronics, with the BMW offering traffic on its navigation system but the C63 offering a better stereo. But the M3 tips the balance with its available double clutch transmission, and the fact that it is about to get a completely redesigned electronics interface and hard-drive-based navigation. If this European refinement isn't for you, however, there's always the Nissan GT-R. All of our staff members agreed that the C63 AMG is an Editors' Choice. We have to ding its performance rating for poor fuel economy, but everything else about the under-the-hood tech blew us away. The cabin electronics are also excellent--the navigation system may lack advanced features, but it is hard-drive based, making for fast route calculation, and the stereo sounds very impressive. The interface design works well, and the exterior looks good. It's not the prettiest car around, but the AMG elements add some nice touches.