The new Audi A6 generation now has a complete line-up. That includes the S6 and RS6 models but there’s a catch as the performance you get will vary a lot on where you live. As you may know, the Audi S6 is now offered in two flavors. In the US, the S6 comes with a V6 petrol engine whereas in Europe customers will have to make due with a diesel alternative. That means, the European S6 has to face the BMW M550d xDrive as its main rival.

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The rivalry between the A6 and the 5 Series goes back a long way. The two have been trading blows for generations now and that’s not likely to change anytime soon. Today, we’re checking out the most recent versions going up against each other. In one corner we have the new Audi S6 with a 3-liter V6 diesel engine good for 350 HP and 700 Nm (513 lb-ft) of torque. According to Audi, the European S6 should do 0-100 km/h (62 mph) in 5.2 seconds and reach a limited top speed of 250 km/h (155 mph).

2018 BMW M550d sedan test drive 23 830x553

On the other side of this comparison we have the BMW M550d xDrive.  Under the hood of the BMW hides a considerably more complicated engine, a 3-liter straight six unit with four turbochargers, developing 400 HP and 760 Nm (560 lb-ft) of torque.

According to the Bavarians, the M550d should be able to reach the 100 km/h (62 mph) benchmark speed in 4.6 seconds, going up to a similarly limited top speed of 250 km/h (155 mph).

Just to be fair, the guys from AutoTopNL brought a Touring M550d to the showdown as the M Performance 5er is also offered in sedan guise. The numbers show both cars a bit off the mark in the 0-100 km/h sprints, with the BMW clocking 4.81 seconds and the S6 doing 5.35 seconds.

Nevertheless, as the numbers suggest, the BMW is obviously the faster car here being nearly half a second faster over the 1/4 mile and reaching 200 km/h (124 mph) nearly two and a half seconds faster.