Manageable but outrageous power is the SLS AMG's other calling card. It's light in weight, heady in output, and it offers rear-wheel drive, with a few traction tricks.
The massive AMG 6.2-liter V-8 is as close to big-block performance as Germany will ever come. "This sensational-sounding powerplant," as Road & Track calls it, cranks out a prodigiously healthy and vocal 563 horsepower, accompanied by 479 pound-feet of torque. This is one engine that talks back when spoken to via throttle-by-wire controls. Automobile says it's "the Tasmanian Devil of the automotive industry; snarling, popping, and barking while spinning up dust clouds and terrorizing anyone within earshot." The vintage metallic ripple that gathers at low speeds opens up to a fantastic howl, giving you plenty of engine note for your entertainment dollar, though it's almost unbelievably docile at a steady 80-mph cruise. Autoblog gets a little too close for comfort with the AMG engine: "Like good sex and serious warfare, it's ballistic, impossible to ignore and utterly engaging," it, er, waxes enthusiastic.
There's no manual shifter to conspire with the engine; just a new seven-speed dual-clutch gearbox takes care of all the gearchanges. Developed by AMG, the four transmission modes include: Comfort, Sport, Sport +, and Manual, with a RACESTART launch-control program. Edmunds observes, "manual-mode shifting is aided by a set of F1-style shift indicator lights." AMG says the gearbox is good for all modes, from "relaxed" driving to track racing, but "relaxed" may be too accurate a word. It certainly slows and mellows shifts when it's in Comfort mode. Racing responses are much quicker, and the paddles themselves have the cool touch of real metal until you've rubbed them warm from repeated 4-3-2 downshifts. Road & Track feels the gearbox "changes gears seamlessly - blipping the throttle on downshifts and grabbing the next gear either at your command or automatically when the tach reaches the redline." However, most reviewers find the SLS' gearbox slow. Motor Trend contends, "After a couple of laps, it's clear this is not the best dual clutch around...rev-matched downshifts send ear hairs quivering, but neither feel as quick as the gear indicator lights claim." Jalopnik reports "Mercedes claims the transmission takes as little as 100 milliseconds to shift, but in practice it feels far slower, with a pronounced delay between a pull of the paddle and the transmission actually doing what you told it to." TheCarConnection.com drove the same test cars and also found them sometimes slow to shift; Mercedes says updates to the software are in the works.
The SLS AMG will accelerate from 0-60 mph in a claimed 3.7 seconds, deeply in Corvette ZR1 territory but shy of the stunning 3.3-second times turned in by the Nissan GT-R and Porsche 911 Turbo. A top speed of 197 mph is also reported.
The SLS's aluminum space frame and body panels give it a relatively light curb weight of 3,573 pounds, and with the midship engine and rear-mounted transaxle, it has nearly ideal weight distribution of 48:52 percent-which makes for better handling than, say, the nose-heavy Dodge Viper. "With a 47-percent front/53-percent rear weight bias," Road & Track observes, "the SLS is a neutral handler that can be coaxed into controllable oversteer with aggressive throttle play." The suspension's forged in aluminum wishbones to handle the startling power with aplomb. "Turn-in is immediate, and chassis balance is brilliant-ask for any amount of oversteer and this two-seater will happily oblige," Automobile states. "Luckily, the steering is quick and accurate, and the brakes instantly responsive and eternally fade resistant." Motor Trend's in sync: "this is some of the best steering feel of a Mercedes-Benz production car to date, possibly the best of any AMG. It's direct, but natural feeling and moderately weighted -- but not artificially so." Autoblog deems the steering "surprisingly sharp and talkative."
When the view ahead widens, it digs into its element. Drive it faster and sweep into tighter turns, and it stays almost completely flat, even while the rear 20-inch tires are clawing for some middle ground between torque and reality. Jalopnik explains, "The 9.5" wide front wheels wearing 265/35 low profiles and 11" rears with 295/30s don't really have an issue with grip. The problem is the 6.2-plus-change-liter (ignore the badges) V8 and its 571 HP just makes pushing the limits of what's possible way too easy."
Ride quality's far better than expected; trundling in traffic can make the SLS seem a touch bouncy, but for a car of its capabilities, it's amazingly controlled. Road & Track reports, "The ride is sports car taut, so over uneven surfaces expect to be jostled, but not uncomfortably so." Motor Trend says "the independently articulating suspension adores well-cambered roads and even sends the SLS sailing effortlessly across less than perfect pavement." Edmunds points out an optional "AMG performance suspension" with stiffer shocks and springs, but advises, "don't rush toward this option if your municipality doesn't fully fund its road maintenance crew."
Carbon-ceramic brakes with 15.4-inch front discs and 14.2-inch rear discs are teamed with 19-inch wheels and tires in front, 20-inchers in back for stopping capability equal to the task. "Massive 4-wheel disc brakes (a carbon ceramic package is optional) provide plenty of stopping power," Road & Track agrees, while Autoblog reports "our car's optional carbon-ceramic brakes were utterly fade- and noise-free on both street and circuit."