To the scientifically minded, the phrase "quicker than the blink of an eye" actually means approximately 360 milliseconds, or 0.36 seconds. To say that each of the 10 throttle butterflies on the new BMW M6's engine open 'quicker than the blink of an eye' would be to do the M division - responsible for developing the tremendous V10 powerplant - an injustice, as they each have the ability to move from shut to fully open in a meagre 120 milliseconds (the throttles, not the boffins...)

As you would expect, the M6 employs the same outrageous 5.0-litre V10 engine as used in the recently launched BMW M5, complete with a rear tyre blistering 507bhp. Headline figures include 0-62mph in 4.6 seconds, and a theoretical top speed exceeding 200mph (the speed is limited to 155mph on customer cars).

Perhaps of more use in the real world, and more so given the M6's weight of over 1700kg, is the fitment of some serious stoppers: no dimensions have been released, but the system includes double piston aluminium callipers and cross-drilled brakes. BMW claims that the M6 will stop from 62mph (100km/h) in just 36 metres, or 140 metres if you happen to find somewhere you can drive at 124mph (200km/h). This equates to a neck-straining 1.3g of deceleration.

More neck exercise will be necessary to put up with sustained cornering in the M6, as the chassis can evidently produce enough grip to build up 1g of lateral acceleration. Though based on the geometry of the 645Ci, there are significant changes to the details. Most of the componentry around the double-arm spring strut front suspension is made out of aluminium, as is the "Integral IV" rear axle. BMW's variable speed-sensing M Differential Lock is fitted as standard to the M6, pushing power to the wheel with more grip under extreme cornering. The tyres themselves have been developed for the M6, and measure 255/40ZR19 and 285/35ZR19 at the front and rear respectively. Reducing unsprung mass further are the bespoke five-spoke 19-inch forged aluminium wheels - they each weigh 1.8kg less than a normal cast alloy wheel would, and look gorgeous to boot.

The M6 is crammed full of driver-centred technology, including the Electronic Damper Control. EDC offers the driver three settings (Comfort, Normal and Sport). The speed-sensitive power steering itself has two settings corresponding to Comfort and Sport on the EDC. Then there is Dynamic Stability Control, which features M Dynamic Mode (as seen on the M5). You've got to love the press release wording on this: "...drivers can take their cars to the limit of the laws of physics, allowing considerable angles of controllable oversteer when circumstances allow." I can't see the advertising watchdogs allowing that into public! Complete hooligans will of course be able to switch the traction control system off completely. You know who you are.

It may sound like there is more focus on the kit than the driver in the M6, and that's before you take into account the 11 (yes, ELEVEN) different change patterns in the Sequential Manual Gearbox. To make life easier, the M6 has been equipped with a "MDrive Manager". The driver uses MDrive to pre-select settings for all the electronic gubbins in one go with a push on the steering wheel-mounted button. So if your commute includes a fast and fun section followed by a built-up area, you can change the whole character of the car to suit each part of your journey.

There are another two driver aids not mentioned yet: the Power button and the Head Up Display. The Power button seems like a waste of time, limiting the engine to 400bhp unless it is pressed. Let's face it; you are as likely to put it in a ditch with 400bhp as you are with the full monty; as is your parking valet. The Head Up Display is infinitely more useful, and is an improvement over the system available on other 5 and 6-series models by now containing more driver-centred information such as engine revs and road speed.

The car pictured here is in Indianapolis Red, one of four exclusive M colours (the others are Sepang Bronze, Interlagos Blue and Silverstone Blue - note the motorsport theme to go along with the F1-inspired V10 configuration). You can just about make out the unpainted carbon fibre roof in the photographs, which is a nice individual touch, as well as shaving 5kg from the highest point of the M6.

Having driven the 630i in Spain last week, and been impressed with its agility and focus on the driver, we are positively salivating at the prospect of testing the M6. Actual dates and prices have not yet been announced, but customers should start receiving their cars before this time in 2005. Let's hope you don't have to wait that long to read our full review. Keep an eye on the main Road Tests page.

Shane O' Donoghue - 15 Dec 2004