One of the world’s most expensive cars just went topless. The Lamborghini Reventon Roadster has been officially unveiled just a few days before the Frankfurt Motor Show kicks off on September 15th. The roadster version of the Lamborghini Reventon will be powered by a 6.5L V12 engine pushing 650HP that will power this beauty to 100km/h in just 3.4 seconds. A genuine supercar in its own right, this one will top out at 211 mph, which we certainly can’t imagine doing with the top down. We’ll likely never have that experience anyway, as only 20 Reventon Roadsters will be produced– and for a costly $1.75 million each. Ouch. [via worldcarfans] View in gallery