Those of you with exceedingly long memories may well recall Audi pushing its Range of five-cylinder petrol cars with the advertising strapline "Drinks like a four, drives like a six." Indeed, this has become something of a Holy Grail amongst engineers, an economical four-cylinder engine with the power of a six. Such quart in a pint pot tactics may not have worked for Audi, who currently have a grand total of zero five-cylinder petrol cars on their books, but Mercedes look to have taken up the baton. Has the Twinpulse engine fitted to the C200K Sports Coupe finally solved the problem?

In short, no. The 1796cc engine fitted to the C200K produces a respectable 163bhp but it's not enough to outsprint even the most modest six-cylinder rivals. Cars like the Hyundai Coupe V6 will show it a clean set of tail pipes and a BMW 130i will have long disappeared by the time the Mercedes has got into its stride. Still, 8.9 seconds to 60mph is fair return especially for a car which returns an average of 36.7mpg. Should you need V6 power in your C-class Sport Coupe, you'll need to stump up £25,530 for the C350 version.

The whole Twinpulse revolution is at first difficult to fathom. Yes, there's some pretty impenetrable technology at work here, but the fact that the C160, C180K and the C200K share the same 1.8-litre four-cylinder engine may lead to some suspicion that we're being 'managed' by Mercedes into potentially paying from £18,555 to £21,005 for what is ostensibly the same car albeit one whose power and torque outputs are dictated by different lines of coding in the engine management software or the bolting on of a supercharger. Look closer and you'll find small differences such as cylinder head design and manifold construction that belie this suspicion.

"Unlike turbocharged cars there's no annoying lag as you wait for the blower to spool up."

It has to be said that the engine plumbed beneath the C200K Sports Coupe's pert bonnet offers a number of advantages over its predecessor. Although the peak power figure remains unchanged, torque is up, fuel economy and emissions are down and the car is quicker. Grumbling suddenly looks a bit churlish. Whilst some of these differences are incremental, the emissions variance is not. Where the old powerplant churned out 237g/km of carbon dioxide, the Twinpulse engine emits just 185, making it a whole lot more affordable for corporate buyers. Likewise fuel economy is transformed, the old car's average of 29.1mpg shamed by the 36.7mpg showing of the Twinpulse C200K.

So what is Twinpulse? It's a raft of changes really, resulting in the twin benefits of higher performance and lower fuel consumption. The smaller engines offer lower friction losses and better thermodynamic efficiency, whilst the Kompressor Eaton-style supercharger has been redesigned with better engineering tolerances and advanced rotor coatings. Crankshaft driven, this supercharger allows the engine to run with wider throttle openings, again improving efficiency. A cylinder head with variable valve timing and double adjustable overhead camshafts are also refinements ushered in with the Twinpulse engine. Smoothness is a given due to two contra-rotating Lanchester balancer shafts, and engine weight has been decreased by 10% through the use of aluminium on items like the crankcase.

So how does it feel on the road? It depends on how you drive. Advanced engine management software means that this car attempts to learn your driving style. Punch the accelerator hard and the response is instant and spiky. Unlike turbocharged cars there's no annoying lag as you wait for the blower to spool up, the C200K offering drive on demand. If you're smoother with the throttle the software takes the edge off the rate the throttle valves are opened, making the car seem creamy smooth. It's an impressive showing. In the latest round of revisions, the suspension pick up points have been tweaked for better driver feedback, the width of the track has grown by 18mm and the steering is also a good deal more direct. Whereas the first Sports Coupes were a little uninvolving, the latest generation promise a good deal more fun.

There won't be a Sports Coupe convertible bodystyle - the CLK really will get to keep that market niche to itself. BMW and Saab - whose products can substantially undercut the CLK Cabriolet but would struggle against a Sports Coupe version - will be delighted to hear it. Not that Mercedes wants to totally ignore the affordable realms of the open-air coupe market. Buyers can also specify Panoramic twin glass sunroofs which extend from the windscreen to the top of the tailgate and slide electrically backwards and forwards. The designers hope that this will create a feeling of light and space - though not too much. To avoid creation of a greenhouse, the panels are smoked and two electrically operated roller blinds can slide across the glass to keep the cabin cool. When you do open up to let in the sunshine, you'll find that the aperture is a third larger than you'd get with a standard sunroof.

The styling on the car has come in for some subtle revisions that most will find it hard to spot. Front bumper and grille have been redesigned for what Mercedes hope is a 'more powerful feel', while clear-lensed headlamps are now fitted as standard. The interior has been given a slight revision too, with a redesigned three spoke sports steering wheel that features silver control buttons, sports seats and silver appliqués in the centre console. The look is still rather generic Mercedes-Benz but at least there's a little more flair evident. Standard equipment includes a full complement of airbags, ABS, remote central locking, climate control and Mercedes' ESP Electronic Stability Programme. If you want more, there's the option of SE trim which adds various other goodies for £700 more or the Sport edition pack.

It's difficult to fault the Mercedes C200K Sports Coupe. It's not the most rewarding driver's car in its class, but it aces the rest as an ownership proposition. The three-pointed star also guarantees great residuals. It may not be a quart in a pint pot but it's certainly a better pint than ever before?

TOP 4 C CLASS DEALS

The results below show the top C CLASS deals on buyacar

	Mercedes-benz C Class C200K Sport 5dr Estate
	ETR	Mthly £440	Saving £2,523	Price £26,072
	Mercedes-benz C Class C200K Sport 5dr Auto Estate
	ETR	Mthly £458	Saving £2,654	Price £27,106
	Mercedes-benz C Class C200 CDI Sport 5dr Estate
	ETR	Mthly £438	Saving £2,527	Price £26,073
	Mercedes-benz C Class C200 CDI Sport 5dr Auto Estate
	ETR	Mthly £454	Saving £2,658	Price £27,092

typical 9.75% APR

PCP finance quote over 48 months,  10,000 miles pa,  deposit of £1000