Porsche specialist 9ff has announced the release of a high-performance tuning pack for the convertible version of the new 911 Turbo. It didn’t take long for the power-hungry guys over at 9ff to transfer their performance know-how from the coupe to the cabrio. The car was only officially launched by Porsche this month, but for some, the thrill of traveling beyond 350km/h with the wind in your hair just can’t wait.

Using knowledge gained from their previous 912hp kit for the Carerra GT and an identical package for the 911 Coupe, 9ff’s engineers then turned to the drop-top. Their previous creation, a 650hp version of the same car managed to reach in excess of 350km/h and Le blog auto believe that this more powerful car will have what it takes to pass 400km/h.

9ff is also concentrating on preparing its custom mid-engined GT9 to challenge the Bugatti Veyron’s title of the world’s fastest production car. Sharing some mechanicals with the 911, the new GT9 is currently being developed at a new facility in Dortmund, Germany, and should be ready in time for a high-speed knock out comp at Italy’s Nardo circuit later this year.

Its makers claim the GT9 is capable of reaching 409km/hh (254mph), 2km/h better than the Veyron’s record of 407.5km/h (253.2mph). Two lucky buyers have already driven away in their own GT9’s, paying upwards of €400,000 for the unique supercar.