Track Tested: 2012 Mercedes-Benz CLS63 AMG

The second-generation Mercedes-Benz CLS-Class lacks the strange and alluring beauty of its predecessor — the new it's-a-sedan-no-really-it's-a-coupe creation doesn't make the same dramatic statement when you pull up in a parking lot. However, Benz still makes a 63 version, and there's plenty of drama when you wood the throttle in the 550-horsepower 2012 CLS63 AMG.

Is it the best-looking luxury-brand four-door on the road? Maybe not, but it will run with a Panamera Turbo (in a straight line anyway), and it's quicker than an E60-generation M5 or the current B7 Alpina.

Vehicle: 2012 Mercedes-Benz CLS63 AMG
Odometer: 4,593
Date: 1/24/2012
Driver: Chris Walton
Price: $126,990

Specifications:
Drive Type: Front engine, rear-wheel-drive
Transmission Type: Seven-speed automatic (with clutch pack in lieu of torque converter) with console shifter and Sport/Competition modes
Engine Type: Twin-turbocharged and direct-injected, DOHC, 5.5-liter V8
Displacement (cc/cu-in): 5,461/333
Redline (rpm): 7,000
Horsepower (hp @ rpm): 550 @ 5,250-5,750
Torque (lb-ft @ rpm): 590 @ 2,000-4,500
Brake Type (front): 14.2-inch, ventilated, cross-drilled carbon-ceramic rotors, six-piston fixed calipers
Brake Type (rear): 14.2-inch, ventilated, cross-drilled carbon-ceramic rotors, four-piston fixed calipers
Steering System: Hydraulic-assist, speed-proportional, power rack-and-pinion power steering
Suspension Type (front): Independent MacPherson struts with dual lower ball joints, coil springs, twin-tube dampers, stabilizer bar
Suspension Type (rear): Independent multilink, air springs, driver-adjustable dampers, stabilizer bar
Tire Size (front): P255/35ZR19 96Y
Tire Size (rear): P285/30ZRF19 98Y
Tire Brand: Continental
Tire Model: ContiSportContact 5P
Tire Type: Summer, asymmetrical
Wheel size: 19-by-9 inches front, 19-by-10 inches rear
Wheel material (front/rear): Forged aluminum alloy
As tested Curb Weight (lb): 4,250 (53.7% front/46.3% rear)

Test Results:

Acceleration:
0-30 (sec): 2.0 (2.3 w/ TC on)
0-45 (sec): 2.9 (3.6 w/ TC on)
0-60 (sec): 4.0 (4.6 w/ TC on)
0-60 with 1-ft Rollout (sec): 3.7 (4.2 w/ TC on)
0-75 (sec): 5.5 (6.1 w/ TC on)
1/4-Mile (sec @ mph): 11.9 @ 121.3 (12.3 @ 121.1 w/ TC on)

Braking:
30-0 (ft): 29
60-0 (ft): 113

Handling:
Slalom (mph): 67.3 (67.3 w/ ESC on)
Skid Pad Lateral Acceleration (g): 0.90 (0.89 w/ ESC on)

Sound:
Db @ Idle: 43.9
Db @ Full Throttle: 76.7
Db @ 70 mph Cruise: 64.7
RPM @ 70 mph: 1,900

Tester's comments:

Acceleration: The trick to getting the most from this car (with traction control disabled) is to find exactly the allowable rate of throttle application that the car can manage at launch (1,500 rpm) and thereafter. This car's 0-60 time is severely restricted by the amount of grip the tires can provide (i.e., I can't go to WOT until midway through 2nd gear). Best run was with zero spin. I sampled the "Race Start" program, but it used 4K rpm to start, allowed too much wheelspin and then short-shifted to 2nd (resulting in a slower 4.6-second 0-60 and a 12.4-second quarter-mile at 120.5 mph). Upshifts are blazingly fast and smooth. Wow.

Braking: Not as short a distance as I would've expected from these brakes, but every stop was absolutely fade-free (feel + distance) and dead straight with no drama whatsoever. Felt like it would do the same stop all day long.

Slalom: With ESC off, the car is limited by front-end grip where understeer begins to crreep in subtly but consistently from cone to cone. The trick becomes precise rotation with lift-throttle without nudging cones with the rear tires — it's a long wheelbase. Firmest setting was too firm and "skiddish." With dampers in medium setting, it didn't acknowledge the dip/hop at cone No. 3. The tires are excellent (predictable breakaway) and allow the chassis to perform at its best. This car must have the optional limited-slip differential (although it's not listed on our test car's monroney), because once the steering was straight, I could wood the throttle at the exit and rocket pas the timers. With ESC in Sport mode, it snubbed understeer, so I didn't need to lift/rotate. Very effective.

Skidpad: With ESC off, the car feels well balanced and begins with a mild understeer condition that only requires throttle steering — I never moved my hands at all. With ESC in Sport, it allowed the same amount of understeer but began to close throttle.