And its philosophy of “one man, one engine,” with each power plant hand-assembled by a single technician, continues today.  Since joining the DaimlerChrysler fold in 1999, the performance division has seen annual sales quadruple to about 20,000 cars worldwide. While these cars seem tailor-made for the autobahn, Americans snap up by far the most, roughly 40 percent.  To see what these mad scientists have wrought, consider that competing performance model lines, which include BMW’s M and Cadillac’s V series, tend to offer two or three models with about 400 horsepower on average. For the United States market, the new hybrid Lexus LS 600h L is the first and only Japanese model to top 400 horsepower.  In contrast, AMG currently offers more than a dozen vehicles and all but a few exceed 500 horses. Three deliver 604 horsepower.  Yet what is a bit strange about this market assault is how Mercedes seems determined to bolt an AMG engine onto every last car (and truck) in its lineup, whether or not it makes sense under traditional rules of performance. Craving a 503-horsepower family S.U.V. or crossover? Step right up for the ML63 and R63. How about a nuclear-powered station wagon with a tiny pair of rear-facing seats? Mr. Cleaver, your E63 wagon awaits.  Then there’s the S65. This 2.5-ton super sedan, with a twin-turbocharged 12-cylinder engine of 604 horsepower, can outrun a Ferrari F430 from the stoplight to 150 m.p.h. — in just 21.1 seconds, according to Car and Driver magazine — as passengers get massaged by their seats while humming along with Wagner coming from the Harmon Kardon sound system.  Yet once I had my fill of mashing the gas and watching the scenery go all hyperspace, the S65 ultimately ranked low on my list of favorite AMGs. Its size prevents this autobahn limo from ever feeling like a sports sedan. At $185,000, this expensive AMG costs as much as his-and-hers versions of the S550, essentially the same fine sedan but with a mere 380-horsepower V-8. When I drove the S65, I had the impression that almost no one could tell it apart from the $88,000 version.  If it’s extra attention you seek, an AMG may not be for you anyway. Cognoscenti can spot their larger wheels, racier bodies and AMG badges from a hundred yards. But many of the lavishly engineered goodies are found under the skin — not only in engines, but in suspensions and brakes so powerful that even the burliest AMGs stop as quickly and surely as many lightweight sports cars. You also get special seats, trim and gauges, but the interiors don’t scream that you’ve spent tens of thousands extra.  To buyers, that subtlety can be part of the attraction. While many AMGs will scorch the road like a screaming yellow Lamborghini, they’re much more likely to fly under the radar. And unlike the crude-riding, scary-handling muscle cars of yore, the AMGs are as smooth and refined as any top luxury car, stuffed with the latest toys and safety technology.  Still, some well-heeled buyers will blanch at the AMG’s huge price premiums over garden-variety Mercedes. Those premiums range from an additional $19,000 for the SLK55 roadster to an eye-popping $96,000 extra for the S65.  No doubt the roughly 400 financial titans worldwide who will spring for an S65 this year are probably buying it with pocket change. But in trying to apply rational thought to which Mercedes will truly emerge as butterflies from the AMG cocoon — in style, performance, attitude and price — a few do stand out.  Among the most seductive are a pair of sedans stuffed with Deutsche dynamite, the E63 and CLS 63. They’re two of many models blessed with AMG’s new 6.2-liter V-8 that’s simply one of the fiercest V-8s ever bolted to a production automobile.  This hand-built beauty, with a 7,200-r.p.m. redline, derives part of its advantage from sheer size: even the sophisticated 10-cylinder engines of BMW and Audi, at a respective 5.0 liters and 5.2 liters, can’t match the Benz in cubic inches, torque or acceleration.  The engine also represents a welcome change in AMG’s performance philosophy. The brand is moving away from supercharging — pumping air into the engine to boost power — in favor of naturally aspirated engines so strong that they don’t need artificial enhancement. The V-8s produce as much power as before, without the upsetting power surges of some supercharged AMGs.  I drove the CLS63 from New York to Pocono Raceway in Pennsylvania, where I also tested other AMGs on a road course that integrates a banked curve and straightway from the speedway’s Nascar oval. And like every other model with the new V-8, the CLS has a way of turning even everyday streets into your own personal racetrack.  (On that note, Mercedes for years has kept the gentlemen’s agreement among German makers — Porsche excepted — to limit top speed electronically to 155 m.p.h. But six AMG models offer a performance package that, along with additional go-fast gear, raises the speed threshold to 186 m.p.h., or 174 m.p.h. for the SLK55. If that electronic tether were eliminated entirely, some AMG models would approach 200 m.p.h.)  Already a somewhat impractical high-profile car, the swoopy CLS made an ideal patient for the doctors at AMG. The operation included the 507-horsepower V-8; an AMG-modified seven-speed automatic transmission, sport seats and amazing brakes with six-piston calipers up front.  While the E63 looks stealthier than the CLS, it proved to be the most entertaining sport sedan I’d ever driven from Mercedes. The surprisingly neutral handling matches its killer V-8.  According to Car and Driver, the E63 runs from 0 to 60 in just 4.2 seconds, a half second quicker than the BMW M5.  Both CLS and E63 cost about $27,000 more than their basic V-8 versions. But they’re priced competitively with luxury performers like the BMW M5 or Jaguar XKR. At the other end of the scale is the new CLK63 AMG Black Series, basically a street version of the current Formula One safety car minus the flashing roof lights. The CLK is the first Black Series car sold in the United States, lighter and racier than your everyday AMG (the first order of business is tearing out the back seat to cut weight).  This apparently costs you a great deal of money. Its price of $138,375 is almost enough to buy three copies of the base-model CLK 350. But don’t listen to me: its run of 350 copies for the United States is nearly sold out. The SL55 ($132,775) and SL65 ($189,375) make some sense, at least by super-rich standards. Hopped-up versions of what’s already a fantasy GT convertible, the basic SL550, they’re a blast to drive. AMG also supplied the supercharged V-8 for the Mercedes McLaren SLR, a scissor-door supercar with a $452,750 starting price (not including gas guzzler tax), up to 650 horsepower and a 209 m.p.h. top speed. A roadster version goes on sale this fall.  Some models seem silly and superfluous. Prime among these is the R63, a racy take on Mercedes’ misbegotten minivan, the slow-selling R-Class. On styling alone, the ML63 S.U.V. whips the R-Class version. But while the nearly $90,000 ML63 accelerates as quickly as you’d expect with 503 horsepower under the hood, it falls short in the critical fun-to-drive department, lacking the zesty handling of a serious performance S.U.V. like the Porsche Cayenne.  Still, AMG’s approach is nothing if not democratic. To wit, why should two-seat sports car buyers have all the fun? Volker Mornhinweg, the Mercedes-AMG chairman, said that the array of choices had helped fuel the exponential growth of AMG.  In fact, my sleeper-model AMG is also the smallest and least expensive: the SLK55. The original SLK was widely derided as soft and feminine. But its current incarnation, the current second-generation SLK350 is a surprisingly legitimate sports car. Bulked up with a 355 horsepower 5.4-liter V-8, the handsome two-seat SLK 55 feels like the modern offspring of a Cobra and a Benz SL. And its $64,600 price isn’t out of line compared with less-powerful models like the Porsche Boxster S.  O.K., granola-eaters, I know what you’ve been dying to ask: What about the gas mileage? Actually, it stinks. E.P.A. economy ratings often fudge the truth, but the AMGs’ numbers may make an oil sheik blush. The CLS63’s rating, for example, is 12 m.p.g. in the city and 18 highway; when I flogged the gas pedal, mileage dipped to 11-12 m.p.g.  As with other performance mavens, Mercedes’ environmental pitch for AMG sounds well-rehearsed and a bit defensive: We’re only giving customers what they want, we don’t actually make that many, we offer economical choices, and did we mention that our competitors get even worse mileage?  Now, on one hand, I feel that any modern car should be able to beat the mileage of a ’72 Cadillac Eldorado. On the other, it’s hard for me to work up much indignation toward cars like these AMGs, especially when I’m the one driving and grinning like an idiot. If they’re indeed socially irresponsible, it’s in the manner of a charming lout whose style and chutzpah lets him get away with anything.  If that means I should be hauled off to the Albert Gore Re-education Camp in fast-warming Siberia, then so be it.  INSIDE TRACK: Rides of the Valkyries.  A chart with a review last Sunday of cars from AMG, the high-performance division of Mercedes-Benz, misstated the size of the V-8 engine in several models. The correct displacement for the E63, CLK63, ML63, CLS63, R63, CL63, S63 and CLK63 is 6.2 liters, not 6.3.  A version of this article appears in print on , on Page AU1 of the New York edition with the headline: AMG: Passcode to Absolute Power in a Mercedes-Benz. Order Reprints| Today's Paper|Subscribe
Once known for conservative sedans and sleepy diesels, Mercedes-Benz is overwhelming the competition when it comes to muscle cars.