Bugatti Bolide merupakan satu pencapaian kejuruteraan yang mengagumkan, menggabungkan enjin W16 yang kuat dengan teknik ringan yang canggih untuk pengalaman trek yang tiada tandingannya. Salah satu ciri utamanya adalah sistem breknya, yang dibangunkan oleh Brembo, yang merupakan sistem brek karbon terbesar yang pernah dibuat oleh syarikat tersebut.
Brembo bekerja rapat dengan Bugatti selama dua tahun untuk mencipta sistem brek yang dapat sepadan dengan prestasi tinggi Bolide. Brek hadapan menampilkan dua caliper monoblok lapan piston dengan pad prestasi tinggi dan cakera karbon yang besar 390×37.5 mm. Brek belakang mempunyai susunan yang serupa, dengan dua caliper monoblok enam piston dan cakera karbon yang besar 390×34 mm. Walaupun saiz mereka besar, caliper dibuat daripada aloi aluminium ringan dan dilapisi dengan nikel untuk prestasi yang optimum.
Mario Almondo, Ketua Pegawai Operasi Brembo, menyatakan kebanggaannya atas pencapaian ini, mencatatkan keperluan kemahiran kejuruteraan untuk membangunkan sistem brek bagi Bolide. Penggunaan sebatian karbon, serupa dengan yang digunakan dalam Formula 1, membolehkan reka bentuk ringan tanpa mengorbankan prestasi.
Reka bentuk ringan ini tidak hanya mengurangkan berat keseluruhan tetapi juga memastikan penyebaran haba yang sangat baik semasa brek yang kuat, mencegah kehilangan brek dan mengekalkan prestasi yang konsisten walaupun dalam keadaan yang getir. Sistem brek ini termasuk silinder induk khas dan bendalir yang dirumus khas, semuanya berfungsi bersama dengan lancar untuk prestasi yang luar biasa di trek.
Bugatti dan Brembo juga bekerjasama dalam mengoptimumkan penyejukan sistem brek, yang penting untuk menguruskan tenaga dari enjin Bugatti W16 yang kuat. Dengan mengalihkan aliran udara secara tepat ke cakera dan pad, sistem ini memastikan prestasi yang optimal semasa sesi trek yang ketat.
Melalui pengujian dan penyempurnaan yang meluas, sistem brek Bolide telah diselaraskan dengan baik untuk berkembang dalam pelbagai keadaan, termasuk senario cuaca basah. Perhatian terhadap butiran ini memastikan bahawa Bolide memberikan prestasi yang luar biasa tanpa mengorbankan keselamatan di trek.
The Bugatti Bolide stands as a testament to automotive engineering, blending the iconic W16 engine with cutting-edge lightweight techniques to deliver an unparalleled track driving experience. At the heart of the Bolide’s performance lies its braking technology, featuring the largest carbon brake system ever produced by Brembo.
Bugatti tasked Brembo with the challenge of creating a brake system that matches the Bolide’s uncompromising nature. Over two years of rigorous testing and development, Brembo engineers collaborated closely with Bugatti to craft a brake system that pushes the boundaries of design and performance.
The Bolide’s front brakes are a marvel of engineering, boasting two eight-piston monobloc callipers with high-performance pads and massive 390×37.5 mm carbon discs. The rear brakes mirror the front setup, featuring two six-piston monobloc callipers and sizable 390×34 mm carbon discs. Despite their imposing size, the callipers are machined from aluminium alloy and nickel-coated for optimal performance.
Mario Almondo, Chief Operating Officer of Brembo Performance, expressed pride in the achievement, highlighting the engineering prowess required to develop a brake system for the Bolide. The use of carbon compounds akin to those in Formula 1 allowed for a lightweight design without compromising performance.
The lightweight design not only reduces overall system weight but also ensures exceptional thermal conductivity for superior heat dissipation during intense braking. This prevents brake fade and provides consistent performance even under extreme conditions.
The holistic approach to the brake system extends beyond callipers and discs, encompassing bespoke master cylinders and specially formulated fluid. Every component works in harmony to deliver exceptional performance on the track.
Collaboration between Bugatti and Brembo also focused on optimising brake system cooling, crucial for managing the energy unleashed by the Bugatti W16 engine. By directing airflow precisely to the discs and pads, the system ensures optimal performance during rigorous track sessions.
Through extensive testing and refinement, the brake system of the Bolide has been fine-tuned to excel in diverse conditions, including wet weather scenarios. This attention to detail ensures that the Bolide remains unrivalled, delivering outstanding performance without compromising safety or security on the track.
Two years ago, at The Quail in California, Bugatti presented a surprise to guests at the famous motorsports gathering. It was the Bolide, just a concept then but the carmaker announced that it would make the car in limited numbers. Response was instantaneous – within a week, all 40 units of the radically light track-oriented Bugatti machine were booked.
Each costing no less than 4 million euros (about RM18.55 million), the Bolide is the most extreme Bugatti ever created. One motoring writer went as far as the describe it as ‘a Thermonuclear Do-It-All Performance Machine’.
The Bolides are still on the production line in France and the first of the cars with the legendary W16 quad-turbocharged engine will be delivered to customers only next year. But you can have a Bolide at your home or office before them – and it will cost you only 50 euros (RM232) which is a lot less too.
The effects of aerodynamics on the car body and influencing how air flows over it have been studied since the 1920s. As designers came to see how certain shapes and features could reduce drag and improve performance in various ways, the styling also evolved… sometimes to extremes as with the teardrop shapes.
The quest to lower wind resistance has never been greater, especially in this age of hybrids and electric cars where every bit of resistance removed means less of the motor’s power is wasted overcoming it.
And while you might think that sportcars, with their high-powered engines, don’t really need the assistance of good aerodynamics, this aspect is even more advanced. Even the Bugatti Bolide, a concept hyper sportscar with a 1,850 ps W16 8-litre engine has many aerodynamic innovations that contribute to its ability to reach a top speed claimed to be well over 500 km/h.
Morphable outer skin
Chief among them is the Dimple Airscoop – a new technology for which a patent application was submitted a few weeks ago by Nils Ballerstein, one of the engineers at Bugatti. Since the beginning of 2020, he has been preparing a doctoral thesis project to develop a special morphable outer skin for the company’s New Technologies department – and this has now been used for the first time in the Bugatti Bolide.
The idea for the invention began in 2019, while Ballerstein was doing his master’s degree thesis. The young engineer was undertaking research for Bugatti, looking at new 3D-printed brake calipers made of titanium which cooled water as it flowed through. In order to improve the heat transfer and dissipate heat more selectively, he used a dimple pattern inside the channels. The rounded dents in the boundary layer produce turbulence – similar a golf ball.
The result was that the fluid mixes better in the channels – and the temperature in the brake caliper drops. “I was positively surprised when I saw the results with the surface patterns. I then wondered whether the same effect couldn’t be achieved with airflow,” recalled Ballerstein.
Same advantages as golf ball design
For non-scientists, the effect of the aerodynamic design is similar that that of golf balls: the dimples on the surface minimise air drag to such an extent that the ball travels about twice as far with the same impact force compared to an identical golf ball without the dimples.
The same principle applies – the dimples create turbulence on the surface of the golf ball so that air adheres better to the surface, thereby reducing the vortex flow in the slipstream of the ball and subsequently also the drag.
Ballerstein simulated test objects with dimple patterns in order to establish a factual basis to underpin his idea. After completing his master’s thesis, he stayed on with Bugatti while also starting his doctorate at the Institute of Aircraft Design and Lightweight Structures at the Technische Universitat (Technical University) Braunschweig in Germany. He sees the Bolide project as a perfect way to advance his idea.
“Everything about the Bolide is exceptional and extreme. The dimples further improve the car’s already excellent aerodynamics, thereby increasing agility and efficiency,” explained Frank Gotzke, Head of New Technologies at Bugatti.
A world first
The morphable outer skin of the intake scoop on the roof is a world first. It ensures active airflow optimisation. When the hypercar is driven at a slow speed, the surface of the scoop remains smooth; at fast speeds, a field of dimples bulges out. The 60 individual elements extend variably by up to 10 mm depending on the speed – if this benefits the driving state.
From about 80 km/h upwards, air is the dominant resistance factor, and from about 120 km/h upwards, the dimples significantly improve the car’s aerodynamics by reducing this resistance. As with the golf ball, the pattern causes a more turbulent boundary layer, which means that the air flowing around it adheres to the surface for longer and does not detach until later. As a result, the detachment and recirculation areas are reduced and the car’s cd value decreases.
In order to respond swiftly to changes in speed, the dimples extend and retract very quickly, within tenths of a second, in the same way as the active rear wing on the Veyron and the Chiron, for example.
10% less drag
The overall result is that the dimples reduce the aerodynamic drag of the scoop by 10% and also decrease lift by 17%. Airflow to the rear wing is also optimised; at 320 km/h, the downforce on the rear wing is 1,800 kgs while on the front wing, it is 800 kgs.
Another benefit is that the lower aerodynamic drag also reduces the car’s fuel or energy consumption. “This is why the new technology is so crucial – not just for Bugatti. Optimised airflow can save energy on all vehicles,” explained Ballerstein. “We’re still in the development phase, but tests so far show that dimples improve aerodynamics, thereby reducing drag and increasing efficiency.”
For a manufacturer to make a production model, the design cannot be too complex so as to not be too expensive to manufacture, and safety and emission regulations also need to be met. Designing a car for track use offer more freedom technical though safety is still important and there are also competition regulations to conform to.
Concept cars are the best then as they can do not need to meet regulations and can be have advanced technology that is still not ready for commercialisation. Typically, they show the design direction of the brand, and perhaps some new ideas being explored.
This is the case with the Bugatti Bolide, which is being presented as the answer to the question ‘what if Bugatti built a radically light vehicle around its iconic 8.0-litre W16 engine?’. The Bolide concept is a track-oriented hyper sportscar derived from production model intended to be the most extreme, uncompromising, fastest and lightest Bugatti concept car in the company’s recent history.
A ‘what if’ experiment
“Bugatti stands for the continuous quest for technological innovations – in alignment with the company’s brand values of excellence, courage, dedication. And Bugatti never stands still. We are perpetually aiming for new and exciting goals, and the question that we always keep in mind is: what if?” said Stephan Winkelmann, President of Bugatti.
“We asked ourselves how we could realise the mighty W16 engine as a technical symbol of the brand in its purest form – with solely four wheels, engine, gearbox, steering wheel and, as the only luxury, two seats. Important aspects of our considerations were fine-tuning our iconic powertrain without any limitations as regards the weight-to-power ratio. These considerations resulted in the Bugatti Bolide.”
Powertrain designed specifically for the racetrack
Explaining the concept further, Stefan Ellrott, member of the Board of Management of Bugatti and Head of Technical Development, said that the Bolide is the ultimate answer to the question of what if Bugatti built a track-focused hyper sportscar that met the FIA’s safety requirements.
“Designed around the W16 powertrain with the minimum body structure and unbelievable performance data. The result: the smallest possible shell for a breathtaking performance vehicle that allows the W16 to truly come into its own,” he explained. “All of Bugatti’s expertise has been condensed into the Bugatti Bolide. It is therefore an innovative information source for future technologies. The Bolide is thus more than just an intellectual exercise.”
In terms of technology and organisation, the Bolide is one of the most ambitious projects for its lead engineer, Frank Gotzke. After playing a crucial role in the development of the Veyron 16.4 and the Chiron, he was given the responsibility for the technical concept of the Bolide. In only 8 months, he created a completely new sportscar around the Bugatti W16 all-wheel drive powertrain, which was highly modified for the project.
The 8-litre 16-cylinder 1,850 ps engine was engineered specifically for use on the racetrack and has an optimised engine and gearbox, especially for higher engine speeds. Among other things, there are 4 specially developed turbochargers with optimised blades in order to build up more boost pressure and power at higher engine speeds. In order to achieve optimum lubrication even under extremely high centrifugal forces, the oil circuit, oil pressure, check valves, baffles, oil tanks, oil reservoirs, and pump design of the dry sump lubrication have been optimised. The weight of the drive system is also significantly reduced.
Instead of water-to-air intercooling, the Bolide has air-to-air intercooling with water pre-cooling for optimal performance on the racetrack. Two water coolers, which are arranged in front of the front axle, provide a more effective radiator system in terms of flow than is customary even in Formula 1. Three air-cooled oil coolers for engine, transmission, and differential with water pre-cooling reduce the temperature, while newly developed and hybrid carbon titanium turbofan radial compressors ventilate and cool the high-performance racing brake system.
In order to achieve a dry weight of 1,240 kgs for that impressive weight-to-power ratio of 0.67 kg per ps, every avenue was explored, both in terms of what is currently feasible and what will be possible in the future. These included expensive features like having all the screw and fastening elements of the made completely out of titanium. In addition, hollow, thin-walled functional components made of an aerospace titanium alloy are used in many places.
A worldwide innovation is the morphable outer skin of the intake scoop on the roof, which provides active airflow optimisation. If the car is driven at a slow speed, the surface of the scoop remains smooth. In contrast, a field of bubbles bulges out when driven at fast speeds. This reduces the aerodynamic drag of the scoop by 10% and ensures a 17% reduction in lift forces. In addition, the flow onto the rear wing is optimised. At 320 km/h, the downforce is at 1,800 kgs at the rear wing and 800 kgs at the front wing.
As in Formula 1, the Bolide uses lightweight brakes with ceramic discs and coatings. The front forged magnesium rims with central lock weigh 7.4 kgs, while the rear ones weigh 8.4 kgs.
Carbonfibre monocoque
The Bugatti team developed a light monocoque made of carbonfibre around the drive. The integral front end flanged to it is also made of high-strength carbonfibres, as are the fully aerodynamically effective underbody and the monocoque itself. The rear frame is designed as a welded steel assembly made of high-strength stainless steel usually found in aviation.
With an overall height of only 995 millimetres, the Bugatti Bolide is exactly the same height as the historic Bugatti Type 35, and about 300 millimetres flatter than the Chiron. Like in an LMP1 racing car, the occupants fold up the doors that are hinged at the front at an angle, sit on a sill that is only 70 mm wide and then position their feet in the interior.
Inspired by X-1 experimental jets
The stylistic challenge was to transform the unyielding demands of aerodynamics and lightweight construction into an aesthetic that reflects the unique Bugatti DNA, but at the same time illustrates the ambition of an impressive weight-to-power ratio. The overall appearance is dominated by air ducts that are more reminiscent of aerodynamically sophisticated Formula 1 racing cars than classic sportscars.
The appearance of the Bolide invokes the so-called ‘X-planes’ of aviation history that pushed the edge of the performance envelope. It is indirectly reminiscent of the Bell X-1 jet aircraft which was flown by Chuck Yeager, who was the first person to break the sound barrier in 1947. The Bolide does not get up to that speed, of course, but it is claimed to be able to go past 500 km/h.
“For the first time, we are showing what the W16 engine is really capable of. We have freed the vehicle of all baggage and have illustrated and combined the engine with the lightest possible chassis to create the ultimate Bugatti and to ensure the ultimate driving experience. With the Bolide, we are presenting our interpretation of a Bugatti track car of modern times to Bugatti enthusiasts all over the world and finally make their most fervent wishes come true,” said Winkelmann, adding that production plans are not decided yet.