CNBC Business | Lifting  the lid

Lifting  the lid

Richard Lofthouse reveals all about the summer’s hottest drop-tops

Roaring into its first summer as the fastest drop-top in the world, there’s nothing quite like the Bentley Continental GTC Speed. On paper, it looks like a modestly tweaked version of the standard Grand Touring Convertible, with 9% more power; 15% more torque; tougher transmission; sharper suspension and more feelsome steering. But the combined effect, when allied to aesthetic touches such as a very discreet spoiler, rifled exhausts and a more upright front grille, is akin to swapping a fine painting for a masterpiece.  

The subjective experience is all very Bentley. Instead of screaming out a scarlet drama called Ferrari, it’s all deep-throated baritone wrapped up in titanium paint shades and diamond-quilted leather seats the colour of ox blood. Pick top gear at a low speed and the enormous exhausts gargle wonderfully, rising to a muscle-bound bellow. By then, you’ve already shrugged aside any national speed limits and left virtually every other car in the world trailing in your wake.  

While several supercars rival the Bentley’s 0-100 km/h time of 4.5 seconds, very few can match its 0-160km/h time of 10.2 seconds. A Porsche 911 or BMW M3 simply wouldn’t keep up; instead you have to look to halo cars like the Bugatti Veyron or to drag strip specials to outpace the big Bentley.  

Except that the Bugatti costs six times more and isn’t a convertible, while drag cars aren’t road legal. In other words, the Bentley is unique. It manages to pit extremes of luxury against extremes of performance, emerging with both intact. An instant classic, this recession-defying über-car is expected to account for over two-thirds of the GTCs sold by Bentley this year, although even the bosses at Crewe, England, have no idea exactly how many they’ll sell having earlier this year shuttered the factory for six weeks to slash production in the face of recession. 

As such, and bearing in mind that Bentley is working on a brand new drivetrain as we write (likely to be a hybrid) the current GTC Speed may mark the high point of a specifically 20th century motoring trajectory. It consisted of designing ever greater mountains of metal propelled by ever more gargantuan engines to relieve the newly wealthy of their spare cash. Certainly this 200mph dinosaur of a convertible is one way to celebrate a recession, but it’s not the future – which opens up new horizons even as it prompts regretful nostalgia. 

Although not meriting direct comparison, BMW’s beautiful new Z4 wrestles with related issues. It’s simultaneously pretty and muscular, having shed the sharpest creases of the last generation Z4 for a more classic pose. Yet weighing a tonne less than the Bentley, it still tips the scales at 1.5 tonnes. My how we’ve all put on weight. The Z4 is longer and fatter than its outgoing predecessor, which was in turn heavier than the original Z3 which came out in 1996 with a relatively modest but light, four-cylinder engine.  

This provokes a crisis if your idea of a roadster is a light, relatively uncomplicated slip of a car that can be chucked around tight bends. BMW has been perfectly upfront about its motivations. Previous owners wanted the security of a folding, metal roof, and the segment benchmarks to beat are the Mercedes SLK and Audi TT. To meet these requirements while still boasting the ‘Ultimate Driving Machine’, BMW has  had to make its roadster larger and more powerful, the smallest engine of the new  Z4 being a 2.5-litre, six-cylinder unit producing 204bhp.  

The next model up offers a three-litre version of the same unit, while the 35i offers an all-new, twin-turbocharged, three-litre unit that can be specified with a double clutch, seven-speed transmission.  

The real revelation of the range is the entry-level, 204bhp 23i model which is  90kg lighter. Fitted with a six-speed, manual transmission and the optional, adaptable M suspension, and you suddenly have a very capable boulevard cruiser with a very capable chassis should you find an open road to hustle along. The surprisingly discreet engine will rev all the way to 7,000rpm. 

BMW has also engineered in a load-through flap to accommodate skis or golf clubs, while the superbly engineered roof retracts in a scant 20 seconds. The hand brake has gone, replaced by an electric switch, allowing you to rest your arm on the transmission tunnel.  

All in all, the new Z4 marks progress in many areas and hasn’t sacrificed its racy soul to accommodate two sets of golf clubs. Yet anyone looking for a purer expression of the roadster formula will still hanker after earlier BMW models, whether in the comparatively rough-hewn Z3M or even the original, E30 3 Series convertible, which (amazingly) was smaller and weighed less than BMW’s current 1 Series convertible.  

If you just want the wind in your hair consider the ultra-chic Fiat 500 convertible or the excellent new BMW Mini convertible. If you want exoticism on a budget consider a used Porsche Boxster, or with a half-Bentley budget shoot for the Morgan Aero 8, which packs a BMW eight-cylinder engine into a package weighing little over a tonne and looks extraordinary. These comparisons actually flatter the Z4, which is still sitting there looking gorgeous. But equally you might want to wait on next year’s launch of the BMW Z2, which will weigh less, use four-cylinder engines and compete head-to-head with the Mazda MX5, still a benchmark in this heavily contested sector.

Bentley Continental GTC Speed 

 Price: €187,100, pre-tax 
Engine: Twin-turbo, 6 litre,12 cylinder 
Power: 610 PS 
Top Speed: 322 km/h 
0-100km/h 4.5 sec 
CO2: 396 
Economy: 16.6 litres per 100km 

We Like: Earth-moving performance 
We Don’t Like: Two and a half tonne weight with fuel consumption to match 
Verdict: Enjoy it while it lasts

BMW Z4 S-Drive 23i 

 Price: from €28,645 
Engine: 2.5 litre, 6 cylinder 
Power: 207 PS 
Top Speed: 243 km/h 
0-100km/h 6.6 sec 
CO2: 199 
Economy: 8.5 litre per 100km 

We Like: Good looks, retracting roof  and maturity 
We Don’t Like: It’s no longer the simple little roadster that the Z3 was, despite being better 
Verdict: Perfect for travelling across France this summer