Engineering

Comparing the Lotus Evija to other cars is 'like comparing a fighter jet to a child's kite'

The Lotus Evija is a forthcoming all-electric hypercar.

Photo courtesy of Lotus Cars

It's sleek and sophisticated. It's also slippery. The Lotus Evija is the first-ever British all-electric hypercar, and it's here to make a statement.

That statement, in large part, is thanks to the car's sophisticated aerodynamics. Richard Hill is a senior engineer with 30 years of experience the brand working on everything from road cars to race cars. As the Chief Engineer of Aerodynamics and Thermal Management at Lotus, he is responsible for making the Evija as slippery as possible.

Lotus Evija

Photo courtesy of Lotus Cars


During a recent interview, Hill shared the vision behind the sleek Evija's design and compared it to the competition.

The overall philosophy in designing the Evija was to do what happens with most new cars, especially supercars, "It's about keeping the airflow low and flat at the front and guiding it through the body to emerge high at the rear. Put simply, it transforms the whole car into an inverted wing to produce that all-important dynamic downforce."

That downforce and the car's technical details are extraordinary says Hill. When asked how the Evija compares to regular sports cars, he replied: "It's like comparing a fighter jet to a child's kite.'' He went further, "Most cars have to punch a hole in the air, to get through using brute force, but the Evija is unique because of its porosity. The car literally 'breathes' the air. The front acts like a mouth; it ingests the air, sucks every kilogram of value from it – in this case, the downforce – then exhales it through that dramatic rear end."

McLaren designed Evija's splitter into three sections. The large central area provides cool air to the battery pack, which is mounted at the car's midpoint, similar to where Audi keep the V12 in its R8. The splitter minimizes the amount of air allowed under the vehicle, which reduces drag, making the car more aerodynamic. It also works to generate downforce.

At the back of the car are Venturi tunnels. Named for Giovanni Battista Venturi, an Italian physicist who first published on them in 1797, Venturi tunnels on the Evija work to reduce the pressure on the car and cut drag. Hill says, "Think of it this way; without them the Evija would be like a parachute but with them it's a butterfly net, and they make the car unique in the hypercar world."

To make the car stick even more to the road, there's a rear wing. It gets deployed into the "clean air" above the car helping the rear wheels stay planted. Lotus has also equipped the car with an F1-style Drag Reduction System, which is a horizontal plane mounted centrally at the rear. This helps the car achieve higher speeds, quicker.

Even the car's chassis plays a part. "The chassis a single piece of moulded carbon fibre for exceptional strength, rigidity and safety," said Hill. "The underside is sculpted to force the airflow through the rear diffuser and into the Evija's wake, causing an 'upwash' and the car's phenomenal level of downforce."

Official coefficient of drag and speed numbers are forthcoming. The model is projected to achieve over 200 mph.

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Nuts & Bolts

 
 

The Lamborghini Huracán STO is the latest addition to the popular Huracán lineup.

Photo courtesy of Lamborghini Automobili

It's the purest concentration of Lamborghini motorsports possible, made into a road car. It has a big engine, wide haunches, and attitude to spare. Power? That's not even a question.

The new Lamborghini Huracán STO brings together the prowess of the Lamborghini Huracán Super Trofeo EVO and GT3 EVO race cars but in a format that makes it a possible daily driver. The Huracán GT3 EVO is noted for its three 24 Hours of Daytona and two 12 Hours of Sebring wins. The Huracán Super Trofeo EVO was designed for the Super Trofeo race series.

Powered by a naturally aspirated V10 engine that puts out 640 horsepower and 416 pound-feet of torque, the rear-wheel drive Huracán STO can take drivers from zero to 62 mph in just 3.0 seconds. It gets from zero to 124 mph in 9.0 seconds. Lamborghini has given the car a top speed of 192 mph.

Lamborghini Hurac\u00e1n STO The hood and fenders of the car have been combined into a one-piece component.Photo courtesy of Lamborghini Automobili

Lamborghini has given the car an increased wheel track, stiffer suspension bushing, specific anti-roll bars, and MagneRide 2.0. These help with its daily drivability. The engine has been calibrated to be responsive with a direct pedal-to-throttle feeling and improved engine sound sharpness at high revs. Gearchange speed has been increased.

Lamborghini has given the car three new driving modes: STO, Trofeo, and Pioggia. The default STO mode is for road driving and fun on curving roads. In Trofeo mode, the car's systems are optimized for dry asphalt and the fastest lap times on the track. Pioggia (rain) mode optimizes traction control, torque vectoring, rear-wheel steering, and the ABS on wet asphalt.

"The Huracán STO delivers all the excitement of a beautifully balanced, lightweight and aerodynamically superior super sports car, mirroring the driving feeling and exhilaration of Super Trofeo, and perfectly set up for the world's most demanding tracks but created for the road," said Maurizio Reggiani, Chief Technical Officer.

"The extensive technical solutions and intelligence gained from both our Super Trofeo and GT3 programs has been refined and embodied in the Huracán STO, allowing the pilot to experience the emotions of a racing driver, daily, in a road-legal Lamborghini super sports car able to take lap records."

Lamborghini Hurac\u00e1n STO The car's wing allows for massive changes in the airflow of the car.Photo courtesy of Lamborghini Automobili

Lamborghini says that every aspect of the car is designed to balance efficiency and weight. The car features a cofango that is a single piece that combines the hood and fender and was inspired by the Lamborghini Miura and Sesto Elemento.

At the rear, a new fender finds its roots in the Super Trofeo EVO and achieves increased downforce and improves aerodynamic efficiency. The revised rear hood has an air scoop that encourages air cooling at the rear underwood. Dedicated air deflectors manage that airflow and help regulate the car's temperature.

This airflow improves the car's cornering ability while the car's adjustable rear wing optimizes aerodynamic balance and drag resistance depending on track characteristics. The Huracán STO achieves the highest level of downforce in its class. Overall airflow efficiency is improved by 37 percent and downforce has been increased by 53 perfect over the Huracán Performante.

More than 75 percent of the car's body panels are made of carbon fiber. The rear fender features a carbon fiber 'sandwich' technique that is traditionally utilized in the aerospace industry. This allows the car to have 25 percent less carbon fiber material while retaining its structural rigidity.

A lightweight windscreen and magnesium rims continue the lightweighing theme, which also carries over to the interior, which is filled with carbon fiber. Its sport seats are made of the material. Carpets have been removed in favor of a carbon fiber floor while the door panels have been made of the material as well.

Owners of the Huracán STO can fully personalize both the exterior and interior of their race car- on-the-road via a rich Ad Personam personalization program, with limitless paint and trim combinations as well as race-style vinyls.

The first customers will take delivery of the new Lamborghini Huracán STO in spring 2021. Pricing for U.S. customers starts at $327,838.

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The Bugatti Bolide is a concept car that pushes the limits of what is possible for the super luxury automaker.

Photo courtesy of Bugatti

What if Bugatti developed a track-focused hyper sports car? Lotus is doing it. So is McLaren. Ferrari and Lamborghini? Been there, done that.

The Bugatti Bolide concept car pushes the limits of what Bugatti is capable of. It's derived from production cars but doesn't stick to the formula. It has a weight-to-power ratio of only 0.67 kilograms per horsepower.

"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.

Bugatti Bolide The car takes its design inspiration from historic planes.Photo courtesy of Bugatti

In the concept, Bugatti has used its 8.0-liter W16 engine, which delivers 1,850 PS (1,824 horsepower) and 1,805 nM (1,364 pound-feet) of torque to move the Bolide1's 1,240-kilogram (2,733-pound) body. Bugatti clocks the model's top speed as being almost on-par with that of Formula One cars, well above 500 kilometers per hour (310 mph) and confirms that the weight and speed do not impact the car's agility.

The Bolide takes 3:07.1 minutes to complete a lap of Le Mans and 5:23.1 minutes to get around the Nordschleife.

"We asked ourselves how we could realize 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," said Winkelmann.

"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. An uncompromising experiment, a thoroughbred, a Pur Sang that, in its brute exclusivity, impresses above all with high performance, low weight, and a driving experience in a whole new dimension. Driving the Bolide is like riding on a cannonball."

Bugatti Bolide The front of the car is very familiar to Bugatti fans.Photo courtesy of Bugatti

Importantly, the car meets FIA's safety requirements. These include HANS device compatibility, an automatic fire extinguishing system, a towing device, pressure refuelling with fuel bladder, central locks for the wheels, lightweight polycarbonate windows, and a six-point harness system.

"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," said Stefan Ellrott, member of the Board of Management of Bugatti and Head of Technical Development.

"In terms of technology and organization, the Bolide was one of the most ambitious projects of my career," says Frank Götzke, head of new technologies at Bugatti. Before working to develop the Bolide1, Götzke played an integral role in the development of the Veyron 16.4 and the Chiron5. It took Götzke just eight months to create the new model.

Modifications to existing equipment include a de-throttling of the intake and exhaust system to allow for faster response. The engine features four newly developed turbochargers that have optimized blades that are designed to build up boost pressure and power while the engine is running at a higher speed. The oil circuit, oil pressure, check valves, baffles, oil tanks, oil reservoirs, and pump design of the dry sump lubrication have been optimized.

Bugatti Bolide The interior of the car is relatively bare bones to assist with lightweighting.Photo courtesy of Bugatti

The Bolide features air-to-air cooling rather than a water-to-air setup. Water is then pre-cooled for optimal performance. Newly developed and hybrid carbon titanium turbofan radial compressors ventilate and cool the high-performance racing brake system.

The engine is a big part of the equation, but not all. In order to achieve such a low power-to-weight ratio, Bugatti had to look for weight savings wherever possible. All screen and fastening elements are made of titanium. Hollow, thin-walled functional components made of an aerospace titanium alloy are used in many places, having been constructed using a 3D printer, which enabled their 0.5 millimeter thickness.

One of the most interesting parts of the Bolide is its roof. Its outer layer is morphable. Bugatti explains: "If the vehicle 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 percent and ensures a 17 percent reduction in lift forces."

The Bolide uses racing brakes with ceramic discs and coatings. The calipers weigh just 2.4 kilograms (5.2 pounds) each. Bugatti has given the model front forged magnesium rims with central lock that weigh in at 7.4 kilograms (15.4 pounds) while the rear rims weigh inn at 8.4 kilograms (18.5 pounds). It rides on very wide tires - 340 millimeters on the front axle and 400 millimeters on the rear.

Bugatti Bolide

Photo courtesy of Bugatti

The car's light monococque is made of carbon while the front end flange is made of the same. The strength of the carbon fibers is akin to what is used in the aerospace industry and is significantly stronger than what can be found in cars on the road today.

Bugatti's speedster is just 995 millimeters (39.1 inches) high, the same height as the historic Bugatti Type 35.

The Bolide is one of the most aerodynamic and challenging models that Achim Anscheidt, director of design at Bugatti, has taken on. His design for the car was inspired by the so-called X-planes of aviation history. This is most apparent at the tail end of the model. It is indirectly reminiscent of the Bell X-1 jet aircraft which was flown by Captain Charles "Chuck" Yeager 1947, the first person to break the sound barrier at Mach 1.06.

Only around 40 percent of the surfaces of the model are painted, coated in a re-interpretation of the historic French Racing Blue.

"Fifteen years ago, Bugatti succeeded in creating a new segment with the Veyron 16.4: that of the superior hyper sports car. With the Chiron launched in 2016, we systematically developed this segment further. The models bear witness to power and elegance, uniquely combining technology, design, luxury, and quality in a hitherto unknown combination," explains Anscheidt. "In contrast, the Bugatti Bolide is an absolute rebel. It is clear to see that its only aim is to convey the pure power of the W16 engine in a visually and technically unadulterated form. Reduced, raw, and authentic – like freshly-caught sashimi".

Whether the Bugatti Bolide will go into series production, has not been decided yet.

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