Confirming earlier rumors that Jaguar is readying an open-top version of its spiciest XK model to date, our spy shooters snagged pictures of a prototype version of the upcoming XKR-S Convertible put through its paces on the Nürburgring race track.

The XKR-S Coupe was revealed at the 2011 Geneva Salon this past March. Predictably, the convertible model will sport the same styling modifications and performance upgrades as the coupe.

On the outside, the XKR-S treatment adds a new front end with a different nose, a redesigned bumper featuring winglets on both corners and a vented hood, while at the back we find a prominent wing and a revised bumper with a diffuser and four tailpipes.

The chunkier side skirts and new alloy wheel designs complete the more aggressive look.

At the heart of the XKR-S Convertible lies a re-tuned 5.0-liter supercharged V8 engine putting out 550-horses and 680Nm (501 lb-ft) of peak torque, while Jaguar’s engineers will also add a lowered sports suspension and a high-performance braking system.

The British firm is keeping its cards close to its chest for now, but we expect to see the XKR-S making its world premiere this year, most likely at the Frankfurt Motor Show in September.

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