Press Release
New Coupe-like CLS Now Supercharged with AMG V8 Power
The Mercedes-Benz CLS55 AMG is making its North American debut this week during news media activities preceding the Los Angeles Auto Show, open to the public January 7-16 at the L.A. Convention Center. Even before the first CLS500 arrives in the U.S., a high-performance CLS55 AMG is being added to the new lineup, and both models are expected to go on sale in the U.S. market early in 2005.The breathtakingly beautiful coupe-like car with four doors now boasts a 469-horsepower V8 engine from AMG, the high-performance division of Mercedes-Benz. AMG has worked its magic on the CLS powertrain, interior and exterior, including AMG sport seats with nappa leather and new-design 19-inch AMG alloy wheels.
More Power and Grace for the Graceful CLS
While the CLS500 will arrive in the U.S. with a 302-horsepower 5.0-liter V8, the new CLS55 AMG is powered by the Engine Technology International magazine's "Best Performance Engine" of 2003 - a supercharged 5.5-liter V8 that makes 469 horsepower and 516 lb.-ft of torque for eye-popping 0-to-60 mph acceleration times of 4.5 seconds! The impressive power of the CLS55 AMG can be attributed to sophisticated supercharger technology that's found in the E55 AMG and SL55 AMG. A belt-driven Lysholm screw-type supercharger is located between the V8 cylinder banks and works together with a special intercooler to ensure low-temperature, high-density intake air.Power is transmitted to the rear wheels via a five-speed AMG Speedshift automatic transmission that can be manually shifted from a either a conventional lever or Formula-1 style gearshift buttons on the ergonomic AMG sports steering wheel.
To give performance-minded drivers total control of shifting, the manual mode of AMG Speedshift doesn't permit any automatic upshifts - even at max engine speed - or automatic downshifts, even under full load. AMG Speedshift electronic control provides 35 faster gear shifts and torque converter lockup from 1st gear.
Beauty That Is More Than Skin Deep
AMG engineers developed a new sports suspension for the CLS55 AMG that's based on the Mercedes-Benz semi-active air suspension. For flatter cornering, the springs, shocks and stabilizer bars are stiffer than on the CLS500. The CLS55 AMG air suspension includes automatic level control that maintains ride height even when the car is loaded with passengers and cargo, and the driver can choose from three sport-comfort settings as well.Speed-sensitive power steering ensures low steering effort for low speed maneuvers such as parallel parking but automatically reduces the steering assist above 60 mph to provide good road feel.
To make sure the CLS55 AMG stops as fast as it goes, giant vented and perforated disc brakes all around feature 14-inch discs and eight-piston calipers up front and 13-inch discs with four-piston calipers at the rear. Staggered 19-inch wheels with 8 1/2 and 9 1/2 inch widths carry 255/35 tires in front and 285/30 at the rear.
To help handle all the power, the ESP system can apply the brakes on just one wheel to transfer torque to the wheels with better traction, achieving much the same effect as a limited-slip differential. Beefier driveshafts, heavy-duty rear suspension parts and a stronger differential housing with cooling fins complete the package.
Powerful Supercharger Nestled in the Notch
The impressive power of the AMG V8 comes through a belt-driven "Lysholm," or screw-type supercharger that spins at over 23,000 rpm, making a maximum pressure of 11.6 psi, or 0.8 bar.The supercharger is not spinning all the time. Depending on engine speed and load, the engine management computer decides whether to engage the supercharger via an electromagnetic clutch. Imperceptible to the driver, this system provides the best of both worlds - the efficiency of a non-supercharged engine at idle and part-throttle as well as the prodigious power of supercharging whenever it's needed.
Air-To-Water Intercooler Also Boosts Power
To improve efficiency even further, an innovative intercooler sits between the cylinder banks and operates as an air-to-water heat exchanger, extracting heat from the compressed air and transferring it to the coolant. Totally independent of the primary coolant circuit for the V8 engine, a separate pump flows water through a special low-temperature cooler located between the air conditioning condenser and the radiator. Also, an engine oil cooler is housed in the front apron.Racing Experience Means Reliability
Nearly all the mechanical components from basic 5.0-liter V8 engine have been modified significantly. Mercedes-AMG's vast experience in high-performance engines for motorsports shows through:- crankcase uses special cross-bolted main bearing caps
- crankshaft with 92-millimeter stroke using modified bearings and more durable material
- pistons specially forged to resist heat and pressure
- oil supply with a new sump and more powerful oil pump
- camshafts with longer-duration valve opening to pack more air and fuel into the combustion chambers
- valve train uses a double spring assembly with lightweight spring retainers
"One Man, One Engine"
To achieve these top power figures, the technicians at Mercedes-AMG build every engine by hand, ensuring precision tolerances. Individual workmanship and skill are paramount: each technician is responsible for a complete engine. With the utmost care, the craftsman installs each and every part himself, from the crankshaft, connecting rods and pistons to the supercharger. When the job is done, a plaque signed by the technician is affixed to the engine.The Sound of Power
The AMG engine's exhaust system is just as sophisticated as the rest of the car. With the exception of the two exhaust manifolds, the complete exhaust systems of each Mercedes-AMG model have been designed specifically for that application. All four catalytic converters are of ceramic material and feature thin-wall technology. Larger surface area in the catalytic converters ensure reduced exhaust back pressure and more rapid heating on a cold start, to benefit both performance and exhaust emissions. The sound emanating from the characteristic, twin-oval AMG tailpipe produces an aggressive exhaust note with a pleasant resonance.Click image for full size Specifications chart
