New wheel design
Frank Heyl and the Technical Development department teamed up to devise a magnesium wheel design featuring optional aero blades for the Pur Sport. Arranged in a ring, the blades guarantee ideal wheel ventilation while also boosting aerodynamics. While the vehicle is in motion the rings fitted to the rim extract air outwards from the wheel where it is immediately drawn towards the rear. This invention prevents adverse turbulence in the wheel area and also improves the flow across the side of the vehicle. A special cover on each of the five wheel nuts minimizes turbulence and adds a final visual touch to the wheel’s design. Cutting the weight by a total of 16 kilograms results in a lower unladen weight and also reduces the unsprung masses of the already ultra-light Bugatti wheels. “All of the modifications make the Pur Sport’s handling more accurate, direct and predictable. Lower unsprung masses result in improved grip because the wheel maintains contact with the road surface more easily. Anyone behind the wheel will immediately feel its lightweight character through bends”, Jachin Schwalbe, Head of Bugatti Chassis Development, adds. An accomplished interpretation of “form follows performance”.
New tire development
Bugatti and Michelin developed the new and exclusive Bugatti Sport Cup 2 R tire in 285/30 R20 dimensions at the front and 355/25 R21 at the rear to match the new Aero wheel design. Thanks to a modified tire structure and a rubber mix that creates more grip, this combination boosts the vehicle’s lateral acceleration by 10% to additionally increase its cornering speed.
Uncompromising chassis and suspension setup
Bugatti specifically configured the chassis and suspension to be uncompromising on winding roads – without any detrimental effect on comfort. A new chassis setup featuring 65% firmer springs at the front and 33% firmer springs at the rear, an adaptive damping control strategy geared towards performance as well as modified camber values (minus 2.5 degrees) guarantee even more dynamic handling and added agility in bends. Carbon-fiber stabilizers at the front and rear additionally minimize roll. “This setup makes the Chiron Pur Sport steer more directly and accurately through bends and maintains the grip levels for a very long time – even at high speeds. In conjunction with 19 kilograms of weight reduction of the unsprung masses the Pur Sport almost glides across roads”, Jachin Schwalbe explains. In addition to the wheels’ weight reduction totaling 16 kilograms, titanium brake pad base panels cut the vehicle’s weight by a further two kilograms while brake discs strike yet another kilogram of the total weight. “These 19 kilograms fully contribute towards the performance. Fewer weight results in more grip and tangibly more comfort, as adaptive dampers are forced to deal with lower masses to thus be able to maintain the wheels’ contact with the road surface more easily”, Jachin Schwalbe adds. Engineers have guaranteed more direct contact with the road surface by making the connection between chassis, suspension and body 130% firmer at the front and 77% firmer at the rear. Apart from the four familiar EB, Motorway, Handling and Sport drive modes, the Chiron Pur Sport features the new Sport + drive mode to make this enhanced performance more emotionally tangible. In contrast to Sport mode, the traction control system kicks into action on dry race tracks at a significantly later point in the new mode aimed at more skilled cornering experts, making it possible for drivers to change their personal driving style even more than before from razor-sharp ideal lines to drifts, also through fast corners.
New transmission development
A new transmission featuring an overall gear ratio that has been configured 15% closer together guarantees even more dynamic handling and further improves the power distribution of the 8.0-liter W16 engine generating 1,500 horsepower and 1,600-newton meters of torque. The vehicle now unleashes its full power at 350 km/h. “We were forced to reduce the speed as a result of the vastly increased downforce, generated by the new rear spoiler”, Schwalbe explains. 80% of the transmission has been revised while the entire gear set including four shafts and seven forward gears has been adapted to the new conditions. “We reconfigured each gear and calibrated new ratios despite this iconic engine boasting an abundance of power. The gears are closer together now to enable shorter gear jumps and also benefit performance. Most of all when coming out of corners the Chiron Pur Sport accelerates even more aggressively in conjunction with the added grip as well as the more direct chassis and suspension”, Gregor Gries says as the Head of Major Assemblies at Bugatti. At the same time, Bugatti has increased the maximum engine speed of the W16 unit by 200 rpm to 6,900 rpm. In conjunction with the closer overall gear ratio, this creates significantly better elasticity. As a result, the Chiron Pur Sport accelerates from 60 to 120 km/h almost two seconds faster than the already lightning-fast Chiron All in all the elasticity values are 40% better compared with the Chiron.
Production output and cost
2020 will be a special year for Bugatti. The French manufacturer based in Molsheim will be delivering the first Bugatti Divo vehicles this year, a creation showcased at Pebble Beach in 2018, as part of a limited small-scale series totaling 40 units. Production of the Chiron Pur Sport will start in the second half of 2020. Limited to 60 units at three million euros excluding VAT. “With the Chiron Pur Sport, we are showcasing an outstanding vehicle that makes your heart race shortly after having started the engine to push the limits of driving physics even further to the limit than any vehicle ever has done before. This means we have come full circle, back to the good, old Bugatti tradition”, Stephan Winkelmann adds confidently.