The 429-hp 4.6-liter V-8 in the CL550 combines numerous advances and twin turbos to deliver 12% more power. Its 516 lb-ft torque peak offers 45% more thrust at just 2,000 rpm. Rapid-multispark ignition can fire up to four times per millisecond, while high-pressure Direct Injection can microscopically fine-tune fuel spray in just 0.1 milliseconds, reducing emissions, fuel consumption and noise. A lightweight diecast-alloy block, quicker and more widely variable valve timing, reduced friction, and clever "on-demand'' ancillary components like the alternator further boost efficiency.
The industry's first 7-speed automatic has been made even smoother, more responsive and more efficient. A wide range of closely spaced gear ratios delivers the ideal response in virtually every driving situation, for relaxed cruising, quick acceleration, and thanks to two overdrive ratios, better highway fuel efficiency. Adaptive logic adjusts the shift points to match your driving style, while paddle shifters on the steering wheel let you enjoy manual-style control anytime you wish.