With 639 horsepower on tap, there was never any question that the Mercedes-AMG GT 63 S 4Matic+ four-door coupe was going to be fast. But to show just how fast, Merc took it to the Nürburgring and clocked a new record... of sorts.

At 7 minutes and 25.41 seconds, the German automaker claims the GT 63 S is now the fastest vehicle with four seats ever to lap the Nordschleife. And it is, technically speaking. But it's not the fastest sedan. And we don't mean just because Daimler calls it a "four-door coupe" instead.

As you may recall, Jaguar set that record with the XE SV Project 8, which lapped the Green Hell last year in just 7:21.23. That's a good four seconds quicker than the new Benz, but here's the catch: when equipped (as the record-setting car was) with the optional Track Package, the super-Jag has just two seats, despite its four doors – the rear bench deleted as part of the weight-saving measures. So while you can even book a ride in the XE SV Project 8 as part of Jaguar's Ring Taxi program, you'll be the only passenger on board.

On top of all that, Jaguar's only building 300 examples of the amped-up performance sedan, while the hi-po four-door Benz is a full production model, and Mercedes will make as many as it can sell. But if we're going to be really pedantic about the classifications, we might want to see what the Project 8 will do at the Ring with the rear seats in place, because something tells us it wouldn't add four seconds to the lap time.