Bugatti’s Chiron is a pure masterpiece where every inch has been meticulously designed and engineered to ensure the car can safely and reliably travel well above takeoff speeds for commercial jets. Bugatti isn’t saying how fast the Chiron will go, though the company does state that the car’s top speed will be “significantly” higher than that of the Veyron, which in Super Sport trim set the current 267.8 mph land speed record for a production car.
The beating heart of the Chiron is its newly developed W-16 engine. The engine matches the quad-turbocharger, 8.0-liter displacement setup of the unit in the Veyron but virtually every element has been redesigned for improved performance. Bugatti quotes official numbers of 1,480 horsepower and 1,180 pound-feet of torque, which is up on even the Veyron Super Sport’s 1,183 hp and 1,106 lb-ft.
The 25 percent jump in power is mainly due to increased boost pressure. To achieve this, bigger turbos were needed. However, to address the issue of lag Bugatti developed a sequential setup where two smaller turbos work at engine speeds of up to 3,800 rpm and then two bigger units take over. Incredibly, the Chiron’s engine delivers its peak torque at just 2,000 rpm and maintains this all the way to 6,000 rpm. Not surprisingly, Bugatti says the power delivery in the car is “absolutely linear.”
There has been a weight penalty with the new setup so to compensate for this greater use is made of lightweight materials such as titanium and carbon fiber. For example, the intake tube, the charge air system and the chain housing are all made of carbon fiber. Lighter yet stronger internals have also been employed, like the specially developed crankshaft.
As anyone who has played around with turbos will know, more charge pressure needs to be matched with increased fuel flow as well as cooling capabilities for the charge air. For the fuel, Bugatti relies on duplex fuel injection with 32 injectors. And for the charge air, complex cooling systems have been employed, which we will get to later.
As a result, more than 60,000 liters of air per minute are pumped through the engine. The coolant pump is also a very high-performance unit. In one minute, it circulates 800 liters of water through the entire engine. At full tilt, we’re guessing the Chiron will empty its gas tank even quicker than the 12 minutes it takes the Veyron.
Another feature that aids power generation is the new titanium exhaust system with reduced exhaust gas back pressure. The system is fully insulated and equipped with four pre-converters and two main catalytic converters which are considerably larger than their predecessors—one of them is six times the size of an average car’s cat. From the catalytic converters, the exhaust gas is fed to a silencer which is extremely light compared with similar units, weighing around 44 lb thanks to titanium construction. The exhaust system is rounded off by six tailpipes, with four routed to the rear and two pointing downwards.
For Bugatti, generating power isn’t the biggest hurdle. The real issue is keeping temperatures cool. According to Bugatti, the Chiron’s engine can generate upwards of 3,000 hp in heat energy all of which needs to be dissipated. The solution are two cooling water loops, a high-temperature loop for engine cooling and a low-temperature loop for the aforementioned charge air. The high-temperature loop features one main and two auxiliary radiators with 37 liters of cooling water which are pumped through the entire cooling loop in about three seconds. The low-temperature loop is equipped with one radiator and has a water volume of 12 liters. This loop prevents the charge air from overheating in stop-and-go driving and urban traffic.
If the three coolers for engine oil, transmission oil and rear axle differential oil are included, together with the two water/air heat exchangers and the hydraulic oil cooler, the cooling system of the Chiron has a total of 10 radiators. A myriad of intakes, ducts and aero elements found throughout the car are used for cooling, reducing drag and boosting downforce. Most of these related to the powertrain are found under the vehicle.
The Chiron features a flat undertray equipped with special air guides in the form of rails, called strakes, as well as active front diffusers. Air outlets for the main radiator are found here. In the central section of the underbody, NACA ducts scoop air inside the car to cool the powertrain. Air being fed into the engine comes from inlets mounted on the side of the car just behind the doors.
Stay tuned as we will be bringing you much more on this fascinating car in the coming days.
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