2007 Mercedes-Benz CLK63 AMG Cabriolet/ML63 AMG

It's no secret there's a momentous battle of brawn brewing between the sporting arms of today's German luxury marques. BMW's M brand, via the M5 and M6, has recently brought to market a naturally aspirated V-10 that pumps out 500 horsepower and 383 pound-feet of torque. Producing 100 horses per liter and a seductive scream up to 8250 rpm, it's arguably more the 10 than V-10. Then there are Audi's S models, which subsequently have responded, "If you can do a V-10, then we can do it better," evidenced by their lighter and torquier Lamborghini-based 5.2-liter mill whose direct injectors motivate the 420-horse S8 and 430-horse S6. Last, but certainly not least, there's Mercedes's AMG wing, which is answering its rivals' V-10 muscle with--get this--a V-8. Come again? Even better, this 6.2-liter motor, unlike the 5.4-liter kompressor before it, breathes naturally yet generates more power--in most cases, more than the competition's V-10s.

Mercedes invited us to sample this V-10-beater from behind the wheel of two new AMG products--the 475-horse CLK 63 Cabriolet and the 503-horse ML63. To say this new V-8 is as flexible as a yoga instructor would be an understatement. Not only does it boast broad power and torque curves, but its applications are seemingly endless: In addition to the two models we drove, Mercedes plans to install the 6.2 in AMG versions of the CLS-, E-, and R-Classes, with more no doubt to follow.

AMG refers to its all-aluminum beast as a "6.3," despite its 6.2-liter displacement. But it's for good reason--Mercedes's 1970 300SEL 6.3, at the time one of the fastest, most powerful sedans in the world, featured a 6.3-liter V-8. Back then, the 300SEL 6.3 made only 300 (SAE gross) horsepower, but it served as the basis for AMG's first race car, the 300SEL 6.8, whose 6.8-liter engine was robust enough for well over 400 horsepower along with a class victory at the 1971 24-hour race at Spa-Francorchamps in Belgium. Consider the 6.3 designation AMG's homage to the car that helped start it all.

Like that 6.8-liter engine, the new 6.2 sports its share of racing technology. Vertical intake and exhaust ports, a variable intake manifold with two internal throttle flaps, bucket tappets in the cylinder heads, variable camshaft adjustment, and a low-friction twin-wire-arc-sprayed coating on the cylinder walls are just a few of the high-tech tidbits that come from the motorsport melting pot. Perhaps more significant is the fact that the 6.2 was designed autonomously by AMG and thus has "no features or shared parts whatsoever in common with other eight-cylinder units by Mercedes-Benz." Naturally, the new powerplant is handbuilt in AMG's Affalterbach engine shop, according to the "one man, one engine" philosophy, which means the engine builder's signature resides on the engine's AMG badge.