FIGHTING TORQUE
BMW and AMG’S 600bhp super-saloons are fresh from their mid-life facelifts. So which now delivers the winning blow?
YEARS AGO, RUMOUR HAD IT THAT AT LEAST ONE car company referred to the button for turning off stability/ traction control as ‘the journalist button’. I’ll wager that was true. Motoring journalists in search of exciting action shots in cars they don’t own will turn off systems designed to save them from crashing. Customers who’ve just paid tens of thousands for their car? Not so much. What, then, to make of the facility to switch a 600bhp, two-ton saloon like the BMW M5 or Mercedes-amg E63 from four-wheel drive to just rear-wheel drive? Some might wonder why this is even a thing, but there’s heritage and a bit of marketing behind it. The M5 and E63 can trace their bloodlines back over 30 years, to when their forerunners were smaller, lighter, less powerful and just rear-drive, because that worked brilliantly. Power outputs have been on a relentless climb ever since, passing through the 400, 500 and now the 600bhp mark, but power is not the issue. It’s the fact that these engines are turbocharged, and turbocharged very effectively, delivering massive, near-instant torque from low revs. The M5 Competition and E63 S are four-wheel drive because the only way to get all that torque to the road is through all four tyres. So, does the option to make these cars just rear-drive add to their enjoyment and appeal? Is a rear-drive M5 Competition churning out 553lb ft at 1800rpm even driveable in the wet? And what about an E63 S with an even more gargantuan 627lb ft from 2500rpm?
There’s a more fundamental question, of course: are the M5 and E63 enjoyable and rewarding as four-wheel-drive supersaloons? They must be compelling in four-wheel drive because that’s how they will be driven most of the time by the vast majority of owners. On a good road they need to feel engaging and rewarding as they deploy all that torque and power to all four wheels.
I confess that, even as a long-standing enthusiast of power oversteer, once I’d got a feel for the scale and mass of the M5 and E63 and felt their full performance, the prospect of going rear-drive in either made my mouth go dry. Despite weighing almost two tons, these fully loaded saloons can lunge to 62mph from rest in less than 3.5sec and forge on to 100mph in around 7.5sec, and, of course, part of the reason they weigh so much is because of the addition of a transfer box, front propshaft, front diff and front driveshafts.
Press the red start button and the M5 Competition bursts into life with an oddly indistinct V8 flourish. Previous turbocharged M5s have used the cabin speakers to generate a more traditional V8 rumble, but the Competition doesn’t seem fussed with that. Its note is lighter and more businesslike with an eager edge. Pretty soon you appreciate that’s a characteristic that permeates the whole car.
Soon after you roll away you’re aware of the steering’s feedback and connection and also the high level of detail to the taut ride; the Competition has stiffer springs, a slightly lower ride height and revised geometry. Adding to the picture, the carbon-ceramic brakes are light and bite keenly from the top of the pedal. They’re part of the optional, £19,000 ‘Ultimate Pack’. Luxuriously equipped it may be, but the M5 Competition feels bright, keen to get going and show what it can do.
There’s no extra torque, but the Competition gets another 24bhp, taking it to 616bhp, and there’s very little delay between throttle demand and delivery despite it being turbocharged. This is especially true when you slot the bespoke M gearlever into manual to arrive at the apex already in the optimum gear for the corner.
At speed, the tautness of the suspension pays dividends, firm wheel control keeping the car poised and level over tricky tarmac, but there’s no disguising the weight; you can sense it over crests and when you dive into corners. In the dry, there’s a lot of grip from the fat Pirellis and the steering gives a bit of feedback so you can sense where the limit of grip is. You can be reassuringly accurate, too, as you need to be hustling a wide, two-ton saloon.
Despite the mass, the M5 feels agile and the speed it will carry, the grip its chassis finds and the amount of performance it can lay down is staggering. You can work the tyres to the limit of grip and then electronic stability control will gently intervene and hold the line, no matter how lead-footed you are. Through a corner the drivetrain will redistribute the torque to use as much as possible, or it will electronically manage it until there is enough grip, and when there is you fire from the corner and up the road like a cannonball.
It’s effective and impressive. But all the while you’re thinking about the elephant in the room: what’s it like in two-wheel drive? Before making the leap you can select MDM and 4WD Sport, which backs off the traction control a little, allowing the back end to slip a few degrees wide under full power. But if you think that’s anything like going just rear-drive, that you’re building a sense of the rear-drive M5, don’t kid yourself – it’s no more like it than bouncing off the diving board is like jumping from the 10m board.
We’re getting ahead of ourselves, though. The Mercedesamg E63 S has had over 600bhp for a while now, and delivers 74lb ft more than the M5 for a stupendous 627lb ft of torque, and all this from a slightly smaller, 4-litre V8 that carries the signature of the man who built it. Like the M5, in the last year the Mercedes has had a cosmetic nip and