The Porsche 911 Turbo Cabriolet is one of the fastest convertibles on sale right now. Powered by a twin-turbocharged 3.8-liter flat-six engine, the standard 911 Turbo Cabriolet generates 572 horsepower and 553 lb-ft of torque, while the more potent 911 Turbo S Cabriolet produces 640 hp and 590 lb-ft. From a standstill, the 911 Turbo Cabriolet will accelerate to 62 mph in 2.7 seconds, while the S version will do the same sprint a tenth of a second slower.

To put Porsche's claims to the test, the guys at AutoTopNL, who love testing cars at ridiculous speeds on unrestricted German autobahns, managed to get behind the wheel of the range-topping 911 Turbo S Cabriolet and test the convertible sports car's acceleration.

Conditions were not ideal. While the publicity photos show the 911 Turbo S Cabriolet being enjoyed on a sunny summer day, the car was driven with the roof down on a wet road during a cold overcast day in December. However, the less-than-ideal conditions proved to be an effective way to demonstrate the car's performance prowess.

With launch control activated, the 911 Turbo S Cabriolet takes off like a missile. 0-62 mph took 2.81 seconds, which is a tenth of a second slower than Porsche claims. Porsche has already demonstrated the 911 Turbo's impressive launch control system on a closed runway, but this is arguably a more impressive feat considering the test was performed on a slippery road.

Porsche's Wet Mode no doubt helped here since it optimizes the traction control and adaptive dampers if it detects wet conditions. Having the roof down would have also affected the car's aerodynamics.

In more ideal conditions, the 911 Turbo S Cabriolet is clearly capable of setting even faster sprint times than Porsche's official figures suggest. Bravely, the driver pushes the 911 Turbo S Cabriolet to 302 km/h - that's 187 mph with the roof down, which couldn't have been comfortable. At that speed, the violent sound of the wind rushing past drowns out the sweet sound of Porsche's flat-six engine. And yet the convertible sports car still isn't being pushed to its limit - Porsche claims the car will top out at 205 mph if you're brave enough.