Bentley's Continental GT V8 is pitch perfect Looking out, we were surprised to see not three svelte sports racing cars braking hard at the end of their charge up the pit straight, but three big and heavy Continental GTs in nose-to-tail formation, lining up for the first corner. Then they rocketed away out of sight, looking for all the world as if they were racing - though, in fact, their professional drivers were merely warming the engines and tyres before we lesser mortals got our chance to take the cars out on the circuit. That fabulous racket from the elegant twinsets of figure-of-eight shaped tailpipes was not, however, as guilelessly authentic as it seemed. The Continental GT V8 sounds as it does because Bentley's engineers laboured for years to create its cry. Like every other element in this highly wrought artifice of a car, the V8"s exhaust note is a studied and calculated creation. In fact, they even subjected it to computer modelling and to the judgment of focus groups to make sure they got precisely the right pitch of burble when the engine was idling, of roar when it was accelerating and of howl when it was full out. Developed hand-in-hand with Audi, the new four-litre, twin-turbo V8 consumes about 50 per cent less fuel than the W12 - though its overall average of 26mpg might still make J Porritt raise a bushy eyebrow or two. A smaller engine, a lighter gearbox, some remapping of software management, tyres that are more eco-friendly - these changes all amount to some significant gains in efficiency. The most important development, however, has been the automatic shutting down of four of the eight cylinders when the engine is running under light throttle use - as in slow-moving traffic. The V8"s overall improvement over the W12 in CO2 emissions then adds up to 40 per cent. This is no Toyota Prius, however. It may cost 10 per cent less than the W12 version but the new V8 Continental GT is about 25 per cent more of a pleasure to drive. On the Circuito de Navarra, it proved possible to chuck it around and even to go sideways through corners with an abandon that no driver would ever risk in the weightier car. Black wheels, air intakes and black radiator grille give it something of a Darth Vader look which might appeal more to the footballers and rap singers who favour Bentleys than to their Wags, but Bentley can't be held responsible for its customers even though the company cherishes them as if they were family. Bentley Continental GT V8 Price (as tested): £123,850 Power: 500bhp 0-62mph: 4.6sec Top speed: 188mph Average fuel consumption: 26mpg CO2 emissions: 246g/km Insurance group:? Rating: (out of five stars)  Porsche 991 911 Price: £81,242 For: Driver delight Against: Family cramps Rating:  Maserati Gran Turismo Price: £84,395 For: Ravishing exterior Against: Soft in the underbelly Rating: 