Bugatti Veyron

Specifications and Performance

The Veyron features a W16 engine—16 cylinders in 4 banks of 4 cylinders, or the equivalent of two narrow-angle V8 engines mated in a "W" configuration. Each cylinder has 4 valves for a total of 64, but the narrow V8 configuration allows two camshafts to drive two banks of cylinders so only 4 camshafts are needed. The engine is fed by four turbochargers and displaces 8.0 L (7,993 cc/488 in³) with a square 86 mm by 86 mm (3.4 in. × 3.4 in.) bore and stroke.

Putting this power to the ground is a dual-clutch Direct-Shift Gearbox computer-controlled manual transmission with 7 gear ratios via shifter paddles behind the steering wheel boasting an <150ms shift time, designed and manufactured by Ricardo of England. The Veyron can be driven by full automatic transmission. The Veyron also features full-time four-wheel drive based on the Haldex Traction system. It uses special Michelin run-flat tires designed specifically for the Veyron to accommodate the vehicle's top speed. Curb weight is estimated at 1,888 kg (4,160 lb). This gives the car a power to weight ratio of 529 BHP/ton.

The car's wheelbase is 2710 mm (106.7 in). Overall length is 4462 mm (175.7 in), width 1998 mm (78.7 in), and height 1204 mm (47.4 in).

The Bugatti Veyron has a total of 10 radiators.

* 3 radiators for the engine cooling system.
* 1 heat exchanger for the air-to-liquid intercoolers.
* 2 for the air conditioning system.
* 1 transmission oil radiator.
* 1 differential oil radiator.
* 1 engine oil radiator.
* 1 hydraulic oil radiator for the spoiler

It has a drag coefficient of 0.36, and a frontal area of 2.07 m2.This gives it a CdA ft² value of 8.02.


Power

According to Volkswagen (and approved by TÜV Süddeutschland) the final production Veyron engine produces 1,001 PS (736 kW/987 hp) and 1,250 N·m (920 ft·lbf) of torque

Top speed

Top speed was initially promised to be 407 km/h (253 mph) but test versions were unstable at that speed, forcing a redesign of the aerodynamics. In May 2005, a prototype Veyron tested at a Volkswagen track near Wolfsburg, Germany recorded an electronically limited top speed of 400 km/h (249 mph). In October 2005, Car and Driver magazine's editor Csaba Csere test drove the final production version of the Veyron for the November 2005 issue. This test, at Volkswagen's Ehra-Lessien test track, reached a top speed of 407.5 km/h (253.2 mph). The top speed was verified once again by James May on Top Gear, again at Volkswagen's private test track, when the car hit 407.9 km/h (253.5 mph), which equated to precisely one-third of the speed of sound at sea level. When getting close to the top speed during the test, May said that "the tires will only last for about fifteen minutes, but it's okay because the fuel runs out in twelve minutes." He also gave an indication of the power requirements, at constant 250 km/h (155 mph) the Veyron is using approximately 270 to 280 horsepower (200 to 210 kW)[16], but to get to its rated 407 km/h (253 mph) top speed required far more from the engine.

Aerodynamic friction or drag is proportional to the square of the speed; for example doubling speed quadruples drag. Work is a product of force applied over a distance travelled. Comparing a vehicle travelling at 100 mph (160 km/h) with one travelling at 200 mph (320 km/h), over a given time (e.g. 1 second), the faster vehicle must overcome 4 times the aerodynamic drag, and travel twice the distance of the slower one. Thus it does 8 times the work of the slower vehicle in that time. As power is work done in time taken it follows that the swifter vehicle, travelling at twice the speed requires 8 times the power of the slower one. German inspection officials recorded an average top speed of 408.47 km/h (253.8 mph)[5] during test sessions on the Ehra Lessien test track on 2005-04-19.

The car's everyday top speed is listed at 375 km/h (233 mph). When the car reaches 220 km/h (137 mph), hydraulics lower the car until it has a ground clearance of about 8.9 cm (3½ inches). At the same time, the wing and spoiler deploy. This is the "handling mode", in which the wing helps provide 3425 newtons (770 pounds) of downheft, holding the car to the road.[13] The driver must, using a special key (the "Top Speed Key"), toggle the lock to the left of his seat in order to attain the maximum (average) speed of 407 km/h (253 mph). The key functions only when the vehicle is at a stop when a checklist then establishes whether the car—and its driver—are ready to enable 'top speed' mode. If all systems are go, the rear spoiler retracts, the front air diffusers shut and the ground clearance, normally 12.5 cm (4.9 in.), drops to 6.5 cm (2.6 in.).


Acceleration

The Veyron has the greatest acceleration of any production car to date, reaching 60 mph (97 km/h) from a standstill in 2.46 seconds.[17] It reaches 100 km/h (62 mph) in approximately 2.5 seconds, which equates to an average acceleration of around 1.18 g. The car is greatly aided in achieving such times by the presence of a four-wheel drive system that permits the transmission of such great amounts of power in the initial stages of acceleration.

The Veyron reaches 200 and 300 km/h (124 and 186 MPH) in 7.4 and 16.7 seconds respectively. According to the February 2007 issue of Road & Track magazine, the Veyron accomplished the quarter mile in 10.2 seconds at a speed of 142.9 mph (230.0 km/h).


Fuel Consumption

The Veyron consumes more fuel than any other production car, using 40.4 L/100 km (6.99 mpg imp/5.82 mpg US) in city driving and 24.1 L/100 km (11.7 mpg imp/9.76 mpg US) in combined cycle[citation needed]. At full throttle, it uses more than 115 L/100 km (2.46 mpg imp/2.05 mpg US), which would empty its 100 L (22 imp gal/26 US gal) fuel tank in just 12 minutes 46 seconds


Braking

The Veyron's brakes use unique cross-drilled and turbine-vented carbon rotors which draw in cooling air to reduce fade. The front calipers have eight[13] titanium pistons and the rear calipers have six pistons. Bugatti claims maximum deceleration of 1.3 Gs on road tires. Prototypes have been subjected to repeated 1.0G braking from 194 to 50 MPH (312 to 80 km/h) without fade. With the car's acceleration from 50 to 194 MPH (80 to 312 km/h), that test can be performed every 22 seconds. At speeds above 124 MPH (200 km/h), the rear wing also acts as an airbrake, snapping to a 55-degree angle in 0.4 seconds once brakes are applied, providing 0.68 Gs (4.9 m/s²) of deceleration (equivalent to the stopping power of an ordinary hatchback).[13] Bugatti claims the Veyron will brake from 400 km/h (249 mph) to a standstill in less than 10 seconds.