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We can't imagine having 780 HP on tap in a convertible, but 9ff has realized the ridiculousness and created what's likely to be the fastest drop-top in the world. The German tuning haus has taken the 997 Porsche Turbo convertible, stroked the 3.6-liter six to four-liters, modified every conceivable part of the motor, all in an effort to reach a top speed of 237 MPH.
On the outside, the only thing that distinguishes the TRC 91 from its "sedate" ancestry is a set of 20-inch rollers, upgraded brakes, a revised front grille to increase airflow, a couple of aero bits and a trunk lid made entirely out of carbon fiber.
The 4.0-liter mill was actually de-tuned from the hardtop model, which creates 910 HP and 671 lb.-ft. of torque, and allows the rear-engined rocket to make it to 60 just after you count to three. Insanity. But it's our kind of madness.
[Source: Motor Authority]