SPY PICS: New 450kW BMW M5

Mercedes-AMG's next E 63 muscle car broke cover for the first time just yesterday and now first images of BMW's direct response – the new-generation M5 super sedan – have arrived in our inbox.

While mainstream versions of the new E-Class are not expected on sale until early next year and the new 5 Series isn't due in European showrooms until the second half of 2016, the new M5 and e 63 are likely to face off globally in 2017.

Little is known about the next M5, but it's likely to take an evolutionary route and pack a more powerful version of the current model's twin-turbo 4.4-litre V8, which comes standard with the high-output 423kW/680Nm Competition Package in Australia.

That means the new M5 could pump out more than 450kW, which should be enough to fend off the next E 63's twin-turbo 4.0-litre V8 sourced from the 375kW AMG GT but tuned to deliver more than the 430kW/800Nm offered by the biturbo 5.5-litre V8 in the existing E 63 S.

Just as the new E 63 will be based on Merc's lighter new MRA platform from the latest C-Class, however, the new 5 Series and BMW's top-shelf M version will also shed weight since they will be based on the same new '35up' chassis architecture that underpins BMW's upcoming 7 Series limousine.

That should bring a significant real-world reduction of about 100kg compared to the current M5's hefty 1870kg kerb weight.

Also like the new E 63, BMW's new M5 – pictured here at the Bavarian car-maker's Nürburgring test centre – will be available with all-wheel drive for the first time, in this case BMW's xDrive system.

Combined with less weight, AWD traction should see both the new M5 and E 63 super sedans dip under the four-second mark in terms of 0-100km/h acceleration for the first time.