GT (2009)

The investment has also made it possible for Bentley to recruit over 400 new staff to Crewe, giving Bentley greater independence and control over its future than at any time since it first passed into proprietary ownership in 1931.

Engine

The heart of the Bentley Continental GT is its 5998cc, four camshaft, 48-valve, twin turbocharged W12 engine. It can now be revealed that its power output, hitherto quoted as 'in excess of 500bhp', is in fact 552bhp (560PS) (411kW) at 6100rpm. Maximum torque is 650Nm (479lb ft) which may sound an impressive enough statistic in isolation but its true significance only become apparent when you learn that it is generated at just 1600rpm. Typically, a performance car engine will force the driver to wait until it is spinning at between 3-5000rpm before it will deliver maximum thrust; in the Bentley Continental GT it's all there at barely more than idling speed. No other car in production makes its torque so instantly accessible.

But this just the start of the story for this engine has other claims to fame beyond its headline-grabbing outputs. Its exterior dimensions, for instance, make it the smallest 12-cylinder engine currently in production, despite its considerable 6-litre displacement. The block is just 513mm long, 715mm high and 710mm wide. This has been made possible entirely by its 'W' formation where instead of arranging the cylinders in two long rows as you would in a conventional V12 configuration, each bank of cylinders is actually staggered, effectively creating two V6 engines mated on a common crankshaft. The angle between the two main banks is 72deg, that between the staggered cylinders just 15deg. The result of this is an exceptionally compact motor, a trait that brings advantages in many areas. Clearly it helps hugely with weight distribution as a geographically small engine is easier to locate nearer the centre of the car. This in turn helps the overall packaging of the car and, in particular, its frontal crash performance, a crucial consideration in a Bentley which has a short front overhang as one of the main features of its design language.

It is no secret that the basic engine architecture has been supplied to Bentley from its parent company, the Volkswagen Group, but by the time Bentley's powertrain team had finished re-engineering it to an exclusive specification for the Bentley Continental GT, it could be truly considered a unique engine in its own right.

Clearly the major engineering challenge was to adapt the engine to accept forced induction, a process that required major re-engineering of the block, the replacement of many internal components and all new inlet and exhaust manifolds. The result would have to cope with a rise in output from 420bhp in standard form to 552bhp once installed under the bonnet of the Bentley Continental GT.

The engine features special pistons, specifically designed for the Bentley Continental GT in order to deliver the desired compression ratio of 9.5:1, a phenomenally high figure for a turbocharged engine. The engine also features seven main bearings, pent-roof combustion chambers and variable valve timing on both inlet and exhaust valves. The timing is infinitely variable within its fixed range, which is some 52 degrees on the inlet camshafts and 22 degrees on the exhaust camshafts.

A huge amount of work was also undertaken to make sure the Bentley Continental GT could use very efficient air to air intercooler. Fitting them within the already cosy confines under the Bentley Continental GT's bonnet was not the matter of the moment, but Bentley's engineers regarded their inclusion in the specification as not negotiable and, after several months work, they were integrated into the under bonnet package.

The Bentley Continental GT also uses a dedicated exhaust system, using two six-into-one manifolds. Much attention has been paid not simply to ensure the exhaust provides maximum efficiency, but also that its sound is appropriate to the fastest Bentley road car in both tone and volume.