This may strike you as a rather startling admission but if it is possible to get bored with massively powerful sports cars, I was getting bored by them. Perhaps I should be a little more specific. I was rather wearied by obscenely powerful Mercedes models that sported the AMG badge. After a conversation to this effect with a senior Mercedes executive, he chuckled and said he had something in store that would change that opinion. At the time I didn't know what he was driving at but the car he had in mind is the latest CLK63 AMG. Is it just another car with an overstuffed engine bay or does it have more thoroughbred characteristics?

Let me give you an example of why I wasn't hugely enamoured of the high-end AMG cars. I was fortunate enough to be given the opportunity to unleash 612bhp worth of Mercedes SL65 AMG on a famous one way derestricted toll road in Germany last year. While this would be the stuff of fantasy for many, the reality never quite measured up. Why? Quite simply the car had too much power for its chassis to cope with. Whole sections of the track were covered with the traction control light flashing wildly. Switch it off and you were at the mercy of a gearbox that would change down mid corner and unleash that torrent of power to overwhelm the rear tyres. The only thing keeping me on the blacktop was some clever coding.

Power may be nothing without control, but this was more of a pitched battle between the engine and the control systems rather than a car that worked all of a piece. The engineers at AMG have gone back to their drawing boards and developed a far more satisfactory solution in the interim. Instead of twin turbochargers that pour an unmanageable tsunami of torque, they have instead resorted to good old fashioned normal aspiration in the CLK63 AMG, a car which uses a big 6.3-litre V8 engine to make the figures. In this case it's a full 481bhp, up from the 362bhp the old 5.5-litre V8 churned out.

"This CLK is a car that does so much more than carry a big stick"

That's still a thunderous amount of power, but control is aided by the fitment of the excellent AMG SPEEDSHIFT 7G-TRONIC transmission. With seven forward speeds and the most spectacularly clumsy name, this is probably the best automatic transmission currently made. No, scrub that. It's undoubtedly the best. Paddles behind the steering wheel allow you to control up and downshifts so that the engine isn't turning on the taps just when you want to rein the car in. Talking of which, the CLK63 AMG also features high performance AMG composite brakes to guarantee retina-detaching retardation.

The engine remains the real star. This is a very different powerplant to those which have gone before it. Instead of using forced induction or relying on low-end lugging power, this 6.3-litre unit is like a scaled-up version of a hot hatch engine. Mercedes call it the high-revving concept and that gives you a clear idea of the character of this engine. Maximum torque doesn't arrive until 5,000rpm at which point you get a generous 630Nm and maximum power arrives at a nosebleed 6,800rpm. The advantage of this is that even before you include any electronic control devices, the throttle pedal travel is acting as a traction control system. It takes some determination to hit 6,800rpm so when you get the goods, you'll probably know all about it. That's a smart move. Cars like the SL65 AMG could give you the most almighty dollop of Newton metres just when you weren't expecting it. The raw figures are impressive, the CLK hitting 60mph in 4.3 seconds and running into its electronic limiter at 155mph. Mercedes Benz engineers reckon that without the limiter, this car would top 190mph, so slippery are its aerodynamics.

Two CLK63 AMG models are on offer here, a coupe version (£65,215) and a Cabriolet (£68,215). Buyers in this bracket expect an awful lot and by and large they get it. In specification terms, just about everything you can imagine is included as standard. Beautiful electrically-adjusted, heated, memory leather seats, a full-house stereo, a trip computer, an amazing climate control system, cruise control and big 18-inch light alloy wheels finished in titanium grey. There's even an AMG RACETIMER function on the instrument cluster to remind you of this car's intent.

The second generation CLK is a better car in every way than its predecessor. There are all kinds of reasons why but probably the most significant is the provision of a body that is a full 40% stiffer. Perhaps most significantly, the stouter platform has enabled the engineers to get rid of the centre pillar between the front and rear windows, a design cue that harks back to classic Mercedes coupe models of the Sixties, a time when the marque was unashamedly a sporting brand. On the move, the absence of that centre window pillar makes more difference than you would credit, allowing a fresh air experience akin to that of a convertible with few of the drawbacks.

Inside, the second generation improvements are small but again, very significant. Where some of the trim in the original version felt a bit down-market, this car has much more in common with the larger S-class-based CL coupe and, like that car (but unlike the C-class Sports Coupe), it can easily seat four adults in long distance comfort. The longer, wider and taller shape helps here, as does the decision to get rid of the central rear seat (instead there's a storage tray) and concentrate on pampering just two rear passengers properly. As you'd expect, this car is full of the kind of sensible features on which Mercedes has built its reputation in recent years.

The CLK63 AMG marks a new direction for powerful Mercedes models. Huge power outputs are, as Mercedes have belatedly realised, no longer enough to sell cars to an increasingly discerning clientele. A full track test awaits but the portents look very good indeed.