Judging by the level of torque they’ve been dealing with, AMG’s drivetrain engineers have had it pretty hard of late. For 27 of the firm’s 33 years, an output of around 500 was the norm.
With the CLK GTR of 1998, that threshold jumped to 800. This car is one of three that raises that bar to four figures.
Newton-metres, mind, not British standard foot-pounds. Nevertheless, the grunt that this S-class packs works out at 738lb ft and that’s plenty. Especially considering that it’s an electronically limited figure: it would serve up 885lb ft of shaft-snapping twist, if only they could find a gearbox capable of transmitting it to the rear wheels.
We’ve encountered Merc’s 5980cc bi-turbo bent 12 before, in the CL 65 AMG, where it played a big part in dispatching the Bentley Continental GT. Unleashed on a derestricted stretch of road, this four-door luxury saloon rockets away just as spectacularly.
An extra 65kg of kerbweight over the CL makes a difference to the numbers, but not to the appreciable performance. A standing kilometre is destroyed in just 22 seconds, just as the speedometer runs into its 155mph limiter. That sort of performance would have been enough for this four-door limousine to make the top five in our ‘200mph club’ supercar test at Nardo last month.
Back on this side of the channel, the S 65 can barely find grip before you end up the wrong side of our loftiest speed limit. Its superpowers are wasted over your average B-road, too: although AMG has done an excellent job tuning the car’s Active Body Control system, neither it, the oversized helm, slow steering rack, nor 390mm brakes are enough to inspire the kind of confidence required to attack a corner in a car this massive.
Turn the ESP stability control system off and, even with most of the car’s 2220kg leaning on its outside rear tyre, there’s enough under your right foot to persuade it to slide sideways: that requires as little effort as it takes to reach down for the seat massager.
Predictably, the S 65 is all about massive autobahn performance without any conceivable compromise. Our test car cost £146,420. That buys the richest pickings of the S-class’ equipment list, including the full COMAND satellite navigation system, a TV, Nappa hide, fully electric, heated seats all round and even a mobile phone. As a percentage of its list price, the optional equipment on this car costs less than it does to spec metallic paint on an entry-level Volkswagen Golf.
Mercedes isn’t selling a short-wheelbase version, so the next-most-expensive S-class is the £92,010 S 600. That is a limousine capable of a similar sub-five second 0-60mph dash and an identical top speed, with a startlingly similar specification, excepting the stealthy AMG makeover.
But if you’re in the rare position of having to justify spending the difference, all you need do is think about it on a pound-per-foot-pound basis. With a Lamborghini Murciélago, you pay £351 for every foot-pound of its bullish torque. For the Bentley Arnage T’s £362 per lb ft you get four seats into the bargain.