Flagship track weapon looks set to raise the roof – or just lose it entirely.
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A drop-top take on the hottest Mercedes-AMG, the GT R, has been spied during development testing.

The AMG GT R Roadster will sit alongside its Nurburgring-conquering coupe sibling, with power from a twin-turbo 4.0-litre V8 making 430kW and 700Nm, sent exclusively to the rear wheels.

That should be good for a 100km/h sprint time of around 3.6 seconds, and a top speed in excess of 300km/h. In other words, fast enough to make your hair stand on end.

Where the regular GT Roadster has a retractable rear spoiler, the GT R is likely to have a bigger, fixed unit down back, as is the case with the coupe. It should also have pumped up guards, designed to house a wider track

There's a mean-looking diffuser complete with a centrally-mounted exhaust, along with wheels from the GT R Coupe. We don't have pictures of the interior, but we'd suggest it'll closely mirror that of the hardtop, with a prominent traction control dial in the middle of the dashboard and racy bucket seats.

Although it hasn't been confirmed, we'd suggest it'll be revealed late this year or early next. Stay tuned for all the latest.