Bragging rights for having the fastest production car is something every high end automobile manufacturer seeks. Since 1998, the automaker McLaren has held that title with the F1 reaching speeds of 240 mph…until now. Bugatti, a child company of Volkswagen, recently released their purebred sports car, the Veyron 16.4. With a price tag of $1,250,000 and a top speed of 253 mph, the Veyron wins the status as the fastest and most expensive production car ever.
To reach this type of speed, it took the most advanced automotive technology along with a couple of engineering miracles from the Bugatti team.
The heart and soul of the Veyron is its 16 cylinder engine. Bugatti managed to pump out 1001 horsepower and 922 pound feet of torque from this monster engine. The first engineering breakthrough was the W design of the engine consisting of four rows of four cylinders. This keeps the engine compact and lightweight. It also uses four turbochargers and an intercooler to feed the engine cool air. But the power doesn't just come out of nowhere; it takes precision timing to make the engine come to life. Bugatti developed a continual electro-hydraulic camshaft setting, which allows for ideal control for the inlet and outlet valves. This special camshaft changes when the intake valve and exhaust valve open and close for optimal performance under certain situations. But a quad-turbocharged engine of this size gets hot; hotter than a dozen pizza ovens. To keep the W-16 running cool, it took a state of the art oil lubrication system and an extensive cooling system. The Veyron cooling consists of three radiators, a heat exchanger, two air conditioning condensers, and separate transmission, differential, and engine oil coolers.
However, having all that power is useless unless you can get it to the ground. To do that Bugatti used a seven speed King Kong transmission and an all wheel drive system. The King Kong allows drivers to operate in automatic or full manual mode. They also needed tires capable of withstanding 250-plus mph speeds while supporting 4800 pounds. This was accomplished using special Michelin PAX System Pilot Sport tires. The PAX system offers exceptional maneuverability and control in the event of a blowout. The Pilot Sport tires are similar to Formula racing tires, which provide exceptional traction and handling in wet and dry conditions.
The Bugatti team had to do a lot of innovative designing with the aerodynamics and drag of the Veyron in order for it to be lightening fast and still be safe. The first thing they did was to allow the Veyron to change its ride height on the fly. Once the car reaches 137 mph, it automatically lowers the ride height from 4.9 inches to 3.1 in the front and 3.7 in the rear. Simultaneously, a small spoiler comes out of the rear bodywork and a wing rises up about a foot. In the front, two underbody flaps open up just in front of the tires blocking the rushing air from hitting the tires. This new setup creates about 330 pounds of downforce in the front and 440 in the rear. But the car will only reach approximately 230 mph in this form. That's because Bugatti makes the drivers come to a complete stop and turn a key in a lock on the floor to get the Veyron into top speed mode. When this is done the cars ride height drops down to a meager 2.6 inches in the front and 2.8 in the rear. At this time, the underbody flaps close, the rear spoiler retracts into the car, and the wing retracts but sticks out of the body at a two-degree angle. This top speed mode reduces the car's drag coefficient from 0.41 to 0.36 and reduces the peak downforce of 770 pounds to 120. These changes make it easier for the Veyron to reach its record breaking top speed; however, they also make it harder to control.
To deal with this problem the people at Bugatti developed some technology to keep the passengers safe. First, as soon as the car is put into top speed mode, it prompts the driver to visually check that all of the aerodynamic changes have been made and that the tire condition and pressure is adequate enough to handle the high speeds. After the driver verifies everything on the checklist, the car is ready for a high speed run; however it will be almost impossible to reach top speed on a public road. This is the result of a safety feature built into the car. This feature takes the car out of top speed mode and returns it to handling mode whenever the steering wheel is turned more than 90-degrees or the brakes are used.
Bugatti put a lot of technology into making the Veyron reach 253 mph, but they also developed some high tech ways to stop it. The first thing they did was to attach huge carbon-ceramic brakes. The front brakes measure in at 15.7 in. and uses four-pad calipers operated by eight pistons. The rear brakes are 15 in. with six-piston, two-pad calipers. To help stop the car at high speeds the rear wing tilts up to a 55-degree angle. This increases the downforce to 1100 pounds and creates 2500 pounds of drag at 230 mph. With all that stopping force, the Veyron is capable of creating 2.00 g of initial deceleration at the 230 mph mark.
The Bugatti Veyron 16.4 was built with one thing in mind-speed. With a price tag of over one million dollars and horrible fuel economy it's not a practical car. But it's a beautifully crafted sports car that can reach 60 mph in just under three seconds and has a top speed of 253 mph limited only by its governor. The fact that Bugatti can do that while keeping it sophisticated, safe, and reliable shows that a dedicated group of engineers can accomplish anything in the automotive world.
Nicholas Rakovec is a third semester student at UW-Madison majoring in mechanical engineering. This is his first semester with the Wisconsin Engineer and is also involved in the Clean Snowmobile Challenge.