Base on the rationalised new S-class, the CL coupe lost 300 kilograms. Part of the weight lost in the reduced dimensions - it is 76mm shorter, 55mm narrower and 54mm lower. Nevertheless, with a bit more study in space efficiency, the rear seat passengers find an extra 11mm leg room compare with the outgoing model.  

Considering the new chassis is 37% stronger than before, you must know most of the weight saving are by means of using lightweight material, such as aluminium, magnesium and plastic. The whole crash-protection structure is still made of conventional steel, but some body panels - such as bonnet, roof and rear fenders - and the mount for engine and transmission are made of aluminium, so is front suspension linkage. The even lighter magnesium is used as the inner panels for doors. Front fenders and boot lid are made of thermoplastic.  

As before, the CL coupe is still a straight-away conversion from the S-class, although 80mm wheelbase was chopped away from the 4-doors. The 306hp 5.0-litre V8, 5 speed automatic (with Tiptronic-style manual override), DISTRONIC cruise control, ventilated plus cooling fan fitted seats are all carried over. What hasn't appeared in the S-class is the Active Body Control (ABC), which uses electronically controlled hydraulic cylinders on each wheel to reduce body roll and pitch. Mercedes claimed it is a world first. Did they forget Citroen's Activa ?  

The only spectacular new item is the new V12 fitted in CL600. It follows the V8 and V6 family, switched to 3 valves per cylinder with single camshaft per bank. A reduction of capacity from 6-litre to 5.8 further reduces the peak power from 394hp to 367hp (the original V12 had 408hp). Torque, though slightly drops on paper, is actually more accessible. However, in terms of emission, the 3-valve design and dual ignition must be superior. In terms of fuel consumption, it improves by a factor of 20%. Another 20% could be saved once the cylinder cut off facility shut down half of the cylinders. 

The second generation V12 also differs from its predecessor by its compactness and lightness. The thin cylinder wall design make it as short as the 5.0 V8, while aluminium block, magnesium intake manifold and hollow camshafts help it to achieve a dry weight of 222kg, versus the old engine’s 411kg. 

Thanks to the massive weight saving, the new car could only be faster.  

No matter V12 or V8, the new CL delivers 155mph top speed, thanks to the electronic cut-out. The V8 accelerates to 60mph in the lower 6th. The V12 may break the 6 second barrier. Based on the S-class, it is not a surprise to find it crosses country with unmatched comfort and refinement. Every departments work smoothly. The ride over low speed bump might be harder than the AIRmatic-equipped S-class, but the ABC counters body roll in corner like a magic. It feels a little bit artificial, but it is really artificial. The speed sensitive and variable ratio power steering might be too light for some, but quick and accurate enough. After all, CL is not designed as a sport-biased coupe. It is a refined and comfortable cross country coupe, a true 4-seater. It is not going to be thrown into corner and expect power slide, nor to expect the at-the-limit feedback from the steering wheel like a Miata MX-5. 

If you are not pleased with its driving behaviour, look at the beautiful interior ! A lot of sophisticated controls there. Feel the ambience of comfort and prestige, plus the style. This is a coupe version of the S-class, not a real GT like the SL. 
 

CL600 and CL55 AMG

Powering the new CL600 is a 5.5-litre twin-turbo V12 capable of delivering a full 500 horsepower, making it more powerful than even Ferrari 456M GT. Even though mated to a compulsory 5-speed automatic gearbox, it can still easily out perform the Ferrari until hitting its speed limiter at 155mph. In particular, 0-60mph takes just 4 and a half second, thanks to that tremendous 590 lbft of torque.  

Of course, the big Mercedes coupe is still very much a luxurious high-speed cruiser, not a real super sports car. Its lower height, lower weight give it an edge over the equivalent S600. ABC offers supple ride at low speed and magical level of stability in corner. However, for its sheer weight and dimensions it never feels as sporty or involving as Porsche 911 Turbo and Maserati 4200GT. The Mercedes never pretend to be, as you can see from its civilized styling. 

Extra body kits help CL55 AMG to get a more aggressive look. Its suspension setup is also stiffer. Power comes from the 5.5-litre supercharged V8 first shown in the SL55. Maximum power is also 500hp, but 516 lbft of maximum torque cannot match the CL600. 

The biggest threat to the CL coupe duo actually comes from SL and S-class. The SL is far more attractive and drives better. Unless you need 2 small rear seats, you will choose the SL over CL. On the other hand, if you need real accommodation and smoother ride without sacrificing much handling ability, S600 will be a better choice. No wonder CL coupe remains to be the slowest-selling model in Mercedes’ line-up. 
 

CL65 AMG

Surprisingly, CL65 has a 6.0-litre engine instead of 6.5-litre. That’s because its internal competitor CL600 already occupied that figure "60" with its 5.5-litre V12. If the parent company do not follow the traditional naming rule according to engine displacement, why should AMG? the AMG engine is based on the same V12 as CL600, with a slight increase of bore and 6mm increase of stroke to take the capacity to 5980cc. Predictably, it has forged pistons, strengthened con-rods and crankshaft and sportier cam profiles to improve output. But most important is to enlarge the 2 turbochargers such that they are capable of charging 1.5 bar boost pressure to the combustion chambers - that’s up from CL600’s 1.0 bar and Maybach’s 1.2 bar. The result is 612 DIN horsepower (or a neat 450kW), from 4800-5100rpm. That place it just behind Ferrari Enzo (660hp) and McLaren-Mercedes SLR (626hp) and equals to Porsche Carrera GT. It also equals AMG’s best effort in its history - the 612hp CLK-GTR. 

However, the CL65 engine delivers its power in a different way from the aforementioned cars. You can easily see that from its torque figure: maximum torque is an astonishing 738 lbft (or a mind-blowing 1000Nm), and that is available from 2000 all the way to 4000rpm ! such a flat curve implies that AMG deliberately limit its torque output to prevent from damaging the Maybach-sourced 5-speed automatic. Engineers said they could get 885 lbft (1200Nm) if it has a suitable gearbox. Anyway, 738 lbft of torque is already comfortably the highest in the world, at least until the arrival of Bugatti Veyron (which is claimed to be 922 lbft). 

So, with so much firepower under the bonnet, can the CL chassis cope? the answer is both yes and no. On the plus side, modern electronics (ASR traction control and ESP stability control) is able to limit wheelspin and oversteer. Active Body Control also saves the need for suspension upgrade. The negative side is that there is not much fun to drive under so much electronic intervention. This car weighs over 2-ton and it is derived from a limousine platform. Fitting a 600-horsepower engine just amplifies its lack of an appropriate chassis. AMG did do a little upgrade. Most obvious is the newly developed Michelin tires which improves steering sharpness a little. The brakes are also upgraded, for instance, the front has a 390mm cast-iron disc clamped by a 8-piston caliper.  

CL65 is an Autobahn kind of supercar. At under 2000rpm, it behaves almost as civilized as the regular CL. Press the throttle deeper, it can beat 911 Turbo and Lamborghini Gallardo in straightline. 0-60mph in 4.4 sec. 0-100 in an estimated 8.8 sec. If you request, AMG can raise the electronic speed regulation from 155mph to 186mph (300kph), yet that is only limited by tires. Engineers said they did 208mph in testing. The most appalling is that it achieves supercar-beating speed at no drama, no fear. CL65 redefines the term "effortless performance".