Autobahns of Austria
Unlike German autobahns, on Austrian autobahns a general speed limit of 130 km/h (81 mph) is set, although as of August 25, 2018, the FPÖ government has been going on a trial for a possible speed limit increase to 140 km/h (87 mph) on the Autobahn 1 freeway. They may only be used by powered vehicles that are designed to achieve at least . While on the motorway voluntary stops, U-turns and backward driving are prohibited.
Formula One car
Top speeds are in practice limited by the longest straight at the track and by the need to balance the car's aerodynamic configuration between high straight line speed (low aerodynamic drag) and high cornering speed (high downforce) to achieve the fastest lap time. During the 2006 season, the top speeds of Formula 1 cars were a little over 300 km/h (185 mph) at high-downforce tracks such as Albert Park, Australia and Sepang, Malaysia. These speeds were down by some from the 2005 speeds, and from the 2004 speeds, due to the recent performance restrictions (see below). On low-downforce circuits greater top speeds were registered: at Gilles-Villeneuve (Canada) 325 km/h (203 mph), at Indianapolis (USA) 335 km/h (210 mph), and at Monza (Italy) 360 km/h (225 mph). In testing one month prior to the 2005 Italian Grand Prix, Juan Pablo Montoya of the McLaren-Mercedes F1 team recorded a record top speed of 372.6 km/h (231.5 mph), which got officially recognised by the FIA as the fastest speed ever achieved by an F1 car, even though it was not set during an officially sanctioned session during a race weekend. In the 2005 Italian GP Kimi Räikkönen of McLaren-Mercedes was recorded at 370.1 km/h (229.9 mph). This record was broken at the 2016 Mexican Grand Prix by Williams driver Valtteri Bottas, whose top speed in race conditions was 372.54 km/h (231.48 mph). However, even though this information was shown in FIA's official monitors, the FIA is yet to accept it as an official record. Bottas had previously set an even higher record top speed during qualifying for the 2016 European Grand Prix, recording a speed of 378.035 km/h (234.9 mph), albeit through the use of slipstream drafting. This top speed is yet to be confirmed by any official method as currently the only source of this information is the Williams team's Twitter post, while the FIA's official speed trap data measured Bottas's speed at 366.1 kmh in that instance. At the moment Montoya's speed of 372.6 kmh (231.5 mph) is still regarded as the official record, even though it was not set during a sanctioned session.