Normally we'd mourn the passing of an engine like AMG's supercharged 5.5-liter V8, the über-huffer that's powered many of our favorite Mercedes-Benzes. However, now that we've sampled its formidable successor, AMG's new naturally aspirated 6.2-liter V8, we've cancelled the wake and are planning a party instead. Woo-hoo! The new 2007 E63 sedan is the most powerful E-Class yet to blast out of Stuttgart, and it's a delight to drive, especially when the 507 horses are fully unleashed.

Some of us had wondered if AMG's new engine, up in horsepower but down in torque, could deliver the heavy boot to the butt of the supercharged sedan. Would it be able to run with the 10-cylinder BMW M5 and Audi S6 sport sedans? This driver discovered the answer — yes! — in a 2007 Mercedes-Benz E63 AMG sedan, appropriately on a stretch of unlimited German autobahn. Underscored by the musical bellow of its big-displacement, race-tech-rich V8, the car rearranged time and distance in exhilarating, entertaining and sometimes frightening ways, shrunk the gaps between here and there to just a few degrees of throttle travel, and obliterated any doubts that the E63 would be as aggressively powerful as the much loved and admired E55.

In only a single respect did it disappoint: Because the sedan achieved the governed top speed of 155 mph so quickly and with such ease, we felt cheated knowing there was so much more top-end power in reserve. Europeans will have the option of ordering their E63s without a limiter; Americans will not. Drat.

By the way, for those who still hanker for force-fed power, the combination of supercharged 5.5-liter engine and five-speed transmission continues in the SLK55 AMG and G55 AMG for the remainder of this model year.

More technology, not much more money
Available as a sedan or wagon, the E63 is expected to retail for about the same price as current E55s, around $83,000, despite the fair amount of new and revised components being introduced across the E-Class line, which in the U.S. consists of the E320 Bluetec sedan, E350 sedan and seven-passenger wagon, E550 sedan and the E63 sedan and wagon.

Befitting their stature at the top of the line, the AMG models benefit from more aggressive running gear, bigger brakes and specific tuning for the Airmatic suspension, and a new seven-speed automatic transmission. The E63 sits on larger 18-inch alloys, 8.5 inches wide up front and 9 inches out back, wrapped by 245/40 and 265/35 ZR-rated tires (Pirelli P Zeros on our test car). We wouldn't mind seeing 19s on this car, both for aesthetic and dynamic reasons.

The bigger brakes consist of front 14.2-inch vented, perforated and partially composite discs gripped by six-piston fixed calipers and 13-inch vented and perforated discs in the rear, clamped by four-piston fixed calipers. Our autobahn runs demonstrated how valuable these big binders are, hauling the heavy sedan down from high speeds time and again with no sign of fade. We also liked the feel from the new electronically controlled hydraulic system, which has eliminated the abruptness that compromised the response of some recent Mercedes brakes.

Though AMG tuned the Airmatic suspension for more aggressive driving, the system still delivers good ride comfort when in comfort mode. Push the adjustable shock button for full sport, and the chassis stiffens to sharpen up the handling, but not at the expense of a harsh ride. Bottom line: There is no other adjustable suspension around that can handle so many kinds of road surfaces and dynamic situations without exposing a weakness.

In fact, perhaps the only shortcoming in the entire vehicle is the seven-speed's lack of a throttle blip when it downshifts. It's possible to accomplish the matching of revs manually by the age-old method of whacking the gas pedal as the tranny makes the move between gears, but we expect that such an advanced gearbox should be able to do it for you.

A faster, less torquey solution
As Inside Line has noted in its review of the ML63 AMG, the new 6.2 is a marvel of an engine. It's lighter, more powerful, cleaner, just as fuel-efficient and, arguably, more durable than the 5.5 it replaces. It's also the first engine in a Mercedes-Benz passenger car to be developed completely by AMG, which fully exercised its motorsport expertise when developing the V8's unique architecture.

In its state of tune for U.S.-bound E63 sedans and wagons, the 6,208cc four-valve DOHC V8 puts out 507 horsepower at 6,800 rpm compared to the E55's 5,439cc three-valve SOHC supercharged V8's rating of 469 hp at 6,100 rpm. Well and good. The newer car should be more powerful. Torque? The bigger V8 twists out 465 pound-feet of torque at 5,200 rpm compared to the (what's this?) 516 lb-ft of torque from the outgoing V8. The E55's torque also peaked earlier, at 2,650 rpm. Sounds like a step backward.

However, there was good reason for the reduction in torque. This allowed Mercedes to fit its new, sophisticated seven-speed automatic in place of the old five-speed. Though the new gearbox is far more efficient than the five-speed, and though it was not built to handle the massive torque of the supercharged engine, its limit of 542 lb-ft, say Mercedes engineers, gives it the required durability to handle the 6.2's far-from-paltry crank twist.

Even better, the loss of torque has had no impact on the car's performance. Let's turn to the factory for this conclusion, which says the 6.2 can launch the E63 sedan from zero to 60 mph in 4.3 seconds. (That's a worthy accomplishment for a 4,035-pound four-door — and it's also probably a conservative figure. Certainly the 514-hp European-spec car we drove in Germany felt much quicker.) To compare, the E55, according to factory numbers, takes 4.5 seconds to achieve the same speed. Race is over; the E63 is quicker. (Just to save you the trouble of looking it up, the similarly sized BMW M5 makes the dash from zero to 60 in 4.5 seconds.) Credit the E63's more efficient seven-speed transmission, improved aerodynamics and, surprisingly in this day of the bloated automobile, a moderate overall weight gain of just 45 pounds compared to the E55 sedan.

We tried a few surreptitious stabs at the low 4s on a narrow side road with all the traction control systems switched completely off, and succeeded only in reaching the limits of adhesion (located just this side of the land of crashes) before we could count off the seconds, scaring ourselves and irking a local farmer tending his hops. We'll wait for our experts and a test track to wring the real numbers out of the 2007 Mercedes-Benz E63 AMG, but note for the record that anyone's skills will have to be on full alert to get the most out of this potent beauty.