Track Tested: 2009 Mercedes-Benz SLK55 AMG

Track Tested: 2009 Mercedes-Benz SLK55 AMG

The 2009 Mercedes-Benz SLK55 is the one of only two AMG models left that doesn't use the latest 6.3-liter V8. Instead, it gets by with an older 5.4-liter V8 that produces 355-horsepower. Sounds meager next to the 500+ horses belted out by the bigger 6.3, but remember this is a 3,500 pound roadster.

Compared to the standard SLK350, the AMG model also gets a fully upgraded suspension, larger wheels and tires, and upgraded brakes. For the record, there's an even more aggressive AMG Performance Package available for an extra $7,000 that adds an even stiffer suspension, new wheels and revised brakes.

Vehicle: 2009 Mercedes-Benz SLK55 AMG
Odometer: 6529
Date: 01/06/09
Driver: Chris Walton


Drive Type: rear wheel drive
Transmission Type: 7-speed Automatic
Engine Type: V8
Displacement (cc / cu-in): 5439cc (332cu-in)
Redline (rpm): 6,600
Horsepower (hp @ rpm): 355 @ 5.750
Torque (lb-ft @ rpm): 376 @ 4000
Brake Type (front): ventilated disc
Brake Type (rear): ventilated disc
Steering System: speed-proportional power steering
Suspension Type (front): MacPherson strut
Suspension Type (rear): multi-link
Tire Size (front): 225/40ZR18
Tire Size (rear): 245/35ZR18
Tire Brand: Pirelli
Tire Model: PZero Rosso MO
Tire Type: performance
Wheel Size: 18 X 7.5 front - 18 X 8.5 rear
Wheel Material (front/rear): alloy
As tested Curb Weight (lb): 3,474

Test Results:

0 - 30 (sec): 2.1
0 - 45 (sec): 3.3
0 - 60 (sec): 4.9
0 - 75 (sec): 6.8
1/4 Mile (sec @ mph): 13.0 @ 108.8
0-60 with 1-ft Rollout (sec): 4.6
30 - 0 (ft): 29
60 - 0 (ft): 115
Braking Rating: Excellent
Slalom (mph): 66.2
Skid Pad Lateral acceleration (g): .87
Handling Rating: Very Good
Db @ Idle: 48.4
Db @ Full Throttle: 80.3
Db @ 70 mph Cruise: 69.1

Acceleration Comments: With ESP on, the traction control system does an admirable job of containing the power. Shutting it off in "Drive Sport" ushered in a 1-2 short shift as the first hint of wheelspin. Had to resort to manual mode to achieve a decent launch, but then the slow tach had it hitting the rev limiter. Difficult, though not impossible, to get under 5.0 to 60mph and in the 12s for the quarter mile. Upshifts are sometimes slow/fast or smooth/harsh and I cannot determine why.

Braking Comments:  Excellent brake power and fade resistance. New zero nose dive and pedal always felt trustworthy. Autobahn brakes.

Handling Comments:  The very definition of "pushy-loose" where it understeers on throttle and snaps into oversteer when you jump out. Tenuous at best and dangerous at worst with ESP off in manual mode.

Like the skidpad, the SLK55 can be a handful in the slalom with ESP off in manual mode. That said, turn-in is crisp up to 9/10ths then starts to understeer. Throttle response is terrific, so a slide at the end is easily requested, but the short wheelbase makes it tricky to control. The PZeros step off pretty abruptly then slide predictably. This is how I imagine a V8 Monster Miata would feel.

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