The ultimate epinephrine-delivery machine and LOUDSYSTEM's next ride Take one good dose of 507 hp and watch the world blur. You'll want to be careful while operating heavy machinery. By Daniel Pund Date posted: 03-28-2007 507 hp, 465 lb-ft - 7-speed automatic transmission - Zero to 60 mph in 4.4 seconds - 14.2-inch front brake rotors If we thought for a moment that our superiors would allow it, our review of the absurdly powerful 2007 Mercedes-Benz CLS63 AMG would consist only of these four words: Whoa...'gain, 'gain, 'gain! So elemental is the appeal of this, this engine with a car attached to it, that even the year-and-a-half-old child riding in the backseat feels it. It was she who uttered those four words, again and again and again. We've driven this $100,000 monument to excessive power for a solid week and burned a shameful amount of gasoline in that time and we can't tell you whether you should buy the 2007 Mercedes-Benz CLS63 AMG instead of the BMW M5 or M6 or Audi S6 or any other car for that matter. What we can tell you is, it's gone now and we don't just miss it; we crave it. We're jonesing for it. We just want a little taste of it again. We have a problem. Eventually, you'll make a spectacle of yourself at GM's Tech Center campus by laying short, traction control-abbreviated patches all over its interior roads, the V8 sounding like rolling thunder. Alongside the road, packs of engineers in khaki pants and golf shirts will gawk. Dude, you so gotta cool out. Lead sled Judging by the number of fastback sedans expected in the next few years (from Aston Martin, Jag and Porsche), we're not the only ones who like the CLS. The CLS63's four cannon-barrel exhaust tips and low-slung, lizardlike stance make clear at first glance what this car is all about. In case you somehow miss these cues, there's the car's square chin, low and jutting, in front of 19-inch aluminum wheels wrapped tightly with a thin layer of Pirelli PZero rubber, plus rear fenders that bulge just enough to confine the 9-inch-wide rear wheels. This is why our first few minutes driving the CLS63 seemed so disappointing. Guiding the car through a parking garage feels like trying to throw a punch under water. It feels unresponsive, leaden and slow. The force required for a given amount of response is higher than you expect. This is the necessary tradeoff you pay to pilot a car capable of great speed with a stability quotient slightly greater than that of a large planet. Make no mistake, the CLS63 has evolved based on the priorities of the unlimited speeds of the autobahn. You might notice that we don't have those here in the U.S. This is, however, a big country, and we have thousands and thousands of miles of emptiness where one can conceivably perform the follow ritual: Pull to a stop. Then, with the same motion and force that you would use to kick-start a motorcycle, try to ram the right pedal through the floor board. That's it. No fancy technique or $200 driving shoes needed. Hell, you can go ahead and leave the largely unobtrusive traction control system on. The seven-speed transmission will take care of itself. Then you sit there for a millisecond as those exhaust pipes pour sound into a big, deep puddle around the back of the car. It's the aural equivalent of the huge plume of smoke that billows from the business end of a rocket immediately before it lifts off. Layered atop the big-bore ruckus is a momentary "Ssssss." That would be the wide rear Pirellis exfoliating their outermost layer. And you're off, accelerating as if the CLS63 left half of its 4,340-pound mass at the starting line. This is about when your lizard brain — that old knot of neurons perched atop the spinal cord like a half-sucked lollipop — goes to work. It's that primeval bit of brain that instinctively understands the CLS63. Forget the big mass of noodle that's developed on top of it, which exists for figuring out wiring diagrams and appreciating great works of art such as Botticelli's The Birth of Venus and Reynolds' Smokey and the Bandit II. Last year's supercharged CLS55 always gave you a thwack in the back but would run out of steam as the revs rose. This big-bore lump just keeps accelerating at a faster rate the faster you go. Keep your foot planted for long enough and the lizard brain is going to order up a large dose of epinephrine. Your heart will thump. Your pupils will begin to dilate. All stomach and intestinal activity begins to shut down. Moments later, you'll do it again. Numbers are so...number-y A low overall height and a tall beltline make the interior feel either cosseting or claustrophobic, depending on your state of mind. It comes as something of a surprise, then, that the new car is no quicker than the CLS55 it replaces, despite a 38-hp advantage. We use a weather correction (a mathematical formula to compensate for varying weather conditions) for our test data, and it's changed slightly since we tested the CLS55 in order to meet newer SAE standards. This calibration anomaly combined with the CLS63's slight weight increase and its greater number of gears (seven versus five) means that the CLS63 and CLS55 performance data is a wash. The CLS63 is a couple of tenths quicker to 60 mph (4.4 seconds versus 4.6) and a tenth slower through the quarter-mile (12.8 seconds versus 12.7). The V10-powered BMW M5's numbers are near identical at 4.8 seconds to 60 mph and 12.8 seconds through the quarter-mile. All three are electronically limited to 155 mph. Mercedes has done a spectacular job of keeping the ride compliant and comfy, even on the stiffest setting of the adjustable dampers. Considering the narrow tire sidewalls and AMG's reputation for a slightly harsh ride, this is an accomplishment. Despite the CLS63's impressive 0.88g of outright tire-stick, it is no boy racer, so its owners shouldn't have to suffer the stiff-kneed ride of one. What's your handle, good buddy? With four exhaust cannons blasting, you will likely recognize the CLS63 with your ears before you do with your eyes. The CLS63 is a good-handling car in the way that 4,340-pound cars with big tires sometimes are. High-speed sweepers are going to take a beating from this car. But agile the CLS is not. The CLS's nose feels heavy through the slalom. A committed nutball with a test facility (or large parking lot) at his disposal can coax the CLS into a drift, but we don't anticipate too many fellows will give this a try. The more nimble M5 gets through our slalom 5-mph faster than the CLS. If you want to scamper down a mountain road, get a Lotus. The CLS63 is a speed sled, pure and simple. That there are really no places in the U.S. to legally sample this car's top speed for more than a moment at a time will become painfully obvious shortly after you take delivery of your CLS63. This fact alone makes it a silly thing to buy. Pretty is as pretty does The juxtaposition of the straight cables, columns and blocks highlights the CLS's sensuous form. But, you say, it's gorgeous. And that's true. This four-door's upper body carves an uninterrupted arc of the type that designers are always going on about — purity of line and all that. And the interior is beautifully crafted. Our only complaint inside is the plank of wood trim on the dash that looks like the result of some sort of rag-based painting technique your aunt learned at The Home Depot. Pretty and powerful, yes it is. But the CLS63 AMG is an unreasonable car by any stretch. It is no faster (because of the electronically limited top speed) than the non-AMG CLS550 that costs about $25,000 less. It's no faster or quicker than the CLS55 AMG that it replaces, but it costs a little more. Though longer and wider than the sedan on which it is based (the E-Class), the CLS seats fewer people, and does so less comfortably. Still, we should get a little more time in the car. No biggie. Maybe give a run or two, you know, just for kicks. We mean for confirmation. What? Dude, it's cool. We can handle it. We're trained professionals. That fast C-pillar, so essential to the look of the CLS, seriously compromises rear-seat headroom. What Works: The motor that just keeps on motoring, just as pretty as other CLSs, smooth ride quality. What Needs Work: You'll have to dab the brakes to enter the expressway. Eventually, you'll develop a tolerance for even this level of acceleration. Bottom Line: The vehicle of choice for burning out the old sympathetic nervous system. Specs & Performance The "6.3 AMG" badge on the flank is one of the very few ways to tell the CLS63 from last year's CLS55. Model Year: 2007 Make: Mercedes-Benz Model: CLS63 AMG Style: 4dr Sedan Base Price: $95,575 Price as Tested: $100,805 Drive Type: Automatic with manual-shift capability Transmission Type: 7-speed Displacement (liters): 6208cc Engine Type: Naturally aspirated V8 Horsepower (hp @ rpm): 507 @ 6,800 Torque (ft-lbs @ rpm): 465 @ 5,200 Braking System: Front ventilated disc - rear ventilated disc Steering System: Speed proportional power steering Suspension Type (front): Independent, double wishbones, pneumatic springs, and stabilizer bar Suspension Type (rear): Independent, multilink, pneumatic springs, and stabilizer bar Tire Size (front): 255/35AR19 96Y Tire Size (rear): 285/30ZR19 98Y Tire Brand: Pirelli Tire Model: PZero Rosso MO Curb Weight (lbs): 4,340 as tested Recommended Fuel: Premium unleaded Fuel Tank Capacity (gal): 21.1 EPA Fuel Economy (mpg): 13 city/20 highway Edmunds Observed (mpg): 19 combined (22 best/15 worst) Performance 0 - 30 (sec): 1.9 0 - 45 (sec): 3.1 0 - 60 (sec): 4.4 0 - 75 (sec): 6.3 1/4 Mile (sec @ mph): 12.8 @ 111.8 30 - 0 (ft): 30 60 - 0 (ft): 118 Braking Rating (Excellent, Good, Average, Poor or Very Poor): Excellent Slalom (mph): 64.4 Skid Pad (g-force): 0.88 Handling Rating (Excellent, Good, Average, Poor or Very Poor): Good Db @ Idle: 46.5 Db @ Full Throttle: 79.4 Db @ 70 mph Cruise: 64 Acceleration: The first run with ESP on proved undramatic but still very quick with a 6.6-second run to 60 mph. With ESP off, launching was a difficult chore with the transmission upshifting from 1st to 2nd gear if there was even a whiff of wheelspin. This "last-resort" transmission-derived traction control is frustrating. Finding the correct rate of throttle application is key to "the" run. Do it right, and the transmission shifts from 1st to 2nd at redline. The car is otherwise reasonably quiet inside while spectators get an earfull of the monster V8. Upshifts are amazingly fast and even strain your neck a little. Braking: Again, pretty undramatic, but thoroughly impressive at the same time. No ABS buzz or hum; it just stops. Seatbelt cinches up under full brake-assist ABS stops. Handling: With a steady throttle and ESP off, there's a bunch of grip that melts into gentle understeer. You can coax a bit of rear slip, but it requires genuine commitment. Also, the same wheelspin-induced upshifts we experienced in acceleration testing flummox attempts at drifting the CLS. In the transitions of the slalom, the car's nose feels heavy and reluctant to bite. Because of this mild understeer, you need to commit to an intended lift-throttle oversteer to get the rear end to rotate. Non-expert drivers will never, ever find the oversteer that's technically possible with nutter throttle modulation.