Brent Romans, Senior Automotive Editor
Along with greasy food, morally corrupt politicians, and that episode of "Gilligan's Island" when Gilligan and Skipper both go completely bald, Americans have always had a particular fondness for midsized sedans with oversized V8 engines. The formula for developing these cars is simple: take a relatively inexpensive and unassuming sedan, plop the biggest V8 possible underneath the hood, and keep it clandestine. Legends produced with this formula include the Pontiac GTO, the Plymouth Roadrunner, and the Chevrolet 396 Chevelle.
But all of those cars are long dead. The last year an American company produced a car based on this formula was 1996. The car was the Chevrolet Impala SS. With stealthy black paint and a 260-horsepower, 5.7-liter V8, the SS was a cult hit. Too bad the 2000 Impala is but a shadow of that car, hobbled with front-wheel drive and an evergreen V6. The big-engine, midsize sedan still exists, but one has to look to Europe in order to find it. Oh, and it's no longer inexpensive. In fact, it's downright budget busting.
The AMG-modified E55 is the big V8-powered midsize sedan from Mercedes-Benz. It starts life as a regular E-Class, then is handed off to AMG, a former semi-independent, Mercedes performance-tuning company, now fully owned by DaimlerChrysler.
The regular E-Class comes with either a 3.2-liter V6 or a 4.3-liter V8. In the E55's case, AMG shoehorns in a modified version of the 5.0-liter V8 engine from the S-Class sedan. Bored, stroked, and fitted with a variety of high-performance parts, the E55's 5.4-liter V8 is mated to an upgraded five-speed automatic transmission. There might be a bit of sneakiness with the badging (Mercedes vehicles are almost always named after engine size, so why isn't the E55 an E54?), but there is no sneakiness with the resulting power. Mercedes lists it at 349 horsepower at 5,500 rpm, and 391 foot-pounds of torque at 3,000 rpm. Compared to a '99 Chevrolet Corvette, the E55 produces 4 more horsepower and 41 more foot-pounds of torque. Wow.
Turn the ignition key, and the whole car twists as the V8 fires. You can feel that there is a big, mean lump of an engine in front of you. But you'll never know it from opening the hood. The V8 is covered with vast swathes of black plastic. You won't be able to tell anything by listening to it, either. If you stand outside the car with the hood open, all you hear is an idling engine that just whirs and clacks. It actually sounds more like a diesel engine.
But it sure isn't a diesel when you step on the accelerator. The automatic transmission, flat torque curve, and curb weight (3,765 pounds) all conspire to make the E55 seem slower than it is. Its power delivery is completely linear, like a passenger airliner at takeoff. Only near redline can you hear proper V8 noises. The trick for realizing speed is to watch the speedometer. Based on numbers from Edmunds.com's performance database, the E55 will turn a zero-to-60 time of 5 seconds flat, and a quarter-mile time of 13.6 seconds. Keep going, and the car accelerates right into its 155-mph electronic speed limiter. We'd like to see a stock Pontiac GTO do that.
The five-speed transmission cracks off wonderful shifts. It actually has a computer that reads driver inputs and adjusts its shift points accordingly. We found the computer to be exceptionally intuitive in all driving conditions. It's always a good mark of an automatic transmission when you don't even notice it, and that's the case here. For slippery road conditions, the transmission can be switched to Winter mode, aiding acceleration from a dead stop. It would be nice to have a sequential-shift option for the transmission, but it is by no means necessary. Gas mileage is acceptable for this type of car, with an EPA cycle of 16/23 mpg.
As you would expect, 391 foot-pounds of torque being transmitted to the rear wheels causes major traction problems. So Mercedes has fitted the E55 with both stability-control and traction-control systems. Mercedes calls them ESP and ASR, respectively. Hitting the ESP button on the console turns off both of them. Do so, and a stern yellow light takes residence in the gauge cluster. "Are you absolutely sure you want to do this?" the light seems to say (think HAL from "2001: A Space Odyssey," but with a German accent). "If you do something stupid, it is your own fault." It seemed to us that ESP was tuned to be very conservative in terms of how quickly it activated to reign in the car. This makes sense from Mercedes' point of view, given the engine's power and the unknown factor of driver skill. However, more skilled drivers will feel limited by ESP in spirited driving, and turning off ESP places the car at unnecessary risk. Something like the "competition mode," a feature found on the Chevrolet Corvette's stability system (a setting between maximum computer override and turning the whole system off), would be welcome on the E55.
In more normal driving situations, the E55 strikes an excellent balance between comfort and handling performance. AMG has equipped the car with stiffer springs, special Bilstein shocks, thicker antiroll bars, and 18-inch wheels with Michelin Pilot XGT Z4 245/40ZR18 tires in front and 275/35ZR18s in back. Make no mistake; the E55 does not ride as nice as a regular E-Class. It doesn't soak up broken pavement as well, and the larger tires generate more road noise. But then, an E320 can't pull 0.88 lateral g, either. The E55 has plenty of grip for cornering, and the oversized brakes haul the car down from speed in exceptional and confident fashion. The steering system is light, and allows easy positioning along curvy roads.
Like all other E-Class sedans, the E55 is capable of transporting five adults. Front-passenger, side, and head airbags are standard, as is antilock brakes. AMG has fitted the car with special leather upholstery trim on the seats, doors and steering wheel. The overall level of quality is good, but it's nowhere near a Lexus LS 400. The seats adjust in just about every direction, but there is no adjustable lumbar support.
We'd gladly take some lumbar support and trade in some of the many buttons found in the E55. There are lots of buttons to chose from. It's a virtual cornucopia of buttons, in fact. And without reading the owner's manual, you won't know what half of them do. Frustrated with all these buttons, we counted them up. The total? Eighty-eight of the suckers for the front passengers. And the little pictograms for the buttons are absolutely no help. Maybe that's why there are separate instruction manuals for the phone, radio, service information, and vehicle care. That's in addition to the standard 173-page owner's manual. It seems that Mercedes understands the manuals might be overwhelming, so it also includes a 25-page "Quick Tips" manual. Jeez, what are we driving, a car or a VCR?
Once sorted, the buttons operate a great sound system and an automatic dual-zone climate-control system. Our test car was also equipped with the optional trunk-mounted CD changer and integrated cellular phone. If there's a mechanical problem (or you stuffed your E55 into a canyon wall because you turned off ESP), Mercedes offers 24-hour roadside assistance. One nice touch is a full-size 18-inch spare tire. Mercedes offers a four-year/50,000-mile warranty.
The E55 didn't attract as much attention as we expected. Its looks are very subtle, and the unwashed masses won't know the difference between it and a regular E-Class. The tip-offs are the AMG-derived sport package exterior visuals, rear deck badge, and AMG insignias on the steering wheel, 18-inch wheels, and gauge cluster. Mercedes says this subtlety is on purpose, which kind of makes sense. If you want to be looked at, buy a Viper. Still, for a car of this type, it seemed to be overly staid. Some additional character wouldn't hurt.
There are two factors to consider in the purchase of an E55. The first is whether an E55 is worth the $20,000 premium over an E430. If you are a practical type of person, we'd say no. The E55 pulls feats unattainable by an E430, but those gains aren't worth the 30 percent price increase. However, we would guess most people looking to buy an E55 are doing so because it's simply the fastest Merc available. In this case, the E55 is a spectacular car. But buyers should also look at the other two ultra-performance sedans competing in this market: the Jaguar XJR and the 2000 BMW M5. Pricing for all three is remarkably similar. The M5 is faster; the Jag has more personality. Pick your $70,000 poison.
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