Lamborghini’s new Huracan mid-engine V10 model has enormous tire tracks to fill. It replaces the Gallardo, which, with 14,022 units produced over a decade, was far and away the most successful Lamborghini model in the company’s history. At the 2014 Geneva Motor Show, Lamborghini revealed that car’s successor, the Huracan LP 610-4.
Impressively, the Huracan promises to better the Gallardo in every category. Following Lamborghini’s current naming convention, the new car is named after a famous Spanish fighting bull, in this case a Conte de la Patilla who was undefeated in fights in August 1879 in Alicante. The alphanumeric suffix refers to the longitudinal powertrain orientation, its horsepower rating, and the number of powered wheels.
While the familiar hexagonal-themed styling and mid-mounted, longitudinal V10 engine are carried over, the Huracan is only available in all-wheel-drive form, with a paddle-shifted dual-clutch transmission, ending the marque’s run of rear-drive cars with gated H-pattern manual shifters.
The 5.2-L V10 engine now carries “Iniezione Diretta Stratificata,” a fuel-injection system with both direct and port injectors. A 180-bar (2600-psi) direct-injection system provides greater efficiency in part-throttle, lower-rpm driving, while the port injectors are superior for wide-open-throttle, high-rpm power, according to Maurizio Reggiani, Research and Development Firector for Automobili Lamborghini SpA. The direct injection permits the engine’s 12.7:1 compression ratio.
The result is about 448 kW (610 hp DIN) at 8250 rpm, with 560 N·m (413 lb·ft) at 6500 rpm. This accelerates the 1422-kg (3135-lb) Huracan from rest to 100 km/h (62 mph) in 3.2 s and to 200 km/h (124 mph) in 9.9 s. Fuel consumption is 12.5 L/100 km on the European driving cycle, representing an 11% improvement over the Gallardo.
The engine’s crankcase is made from an aluminum-silicon alloy using low-pressure gravity die casting that the company says ensures a high level of homogeneity. The high silicon content makes the bare cylinder bores hard enough to resist wear without the use of sleeves. It does use cast iron for the main bearing caps to reduce thermal expansion and reduce play in the main bearings.
All four camshafts have 42 degrees of adjustability to match cylinder filling and exhaust demands. A plastic intake plenum contains a two-stage path for variable airflow. At low speeds, the intake channels induce a cylindrical rotation in the air charge for more tumble entering the cylinders. At higher speeds, flaps open for more direct flow and contribute to a deeper sound.
The dual-clutch transmission is a seven-speed unit controlled by steering column-mounted paddles. The Gallardo had an automated manual transmission as its automatic-shifting option vs. the standard H-pattern manual. The Huracan, in contrast, features a modern, smooth-shifting dual-clutch design that, at 60 cm (24 in) in length, is remarkably compact.
It sends power to all four wheels, a traditional Lamborghini option since the 1993 Diablo VT, now made standard equipment. The Huracan’s system uses an electronically controlled and hydraulically actuated multiplate clutch to distribute torque front and rear, replacing the viscous coupling used in the Gallardo.
Normally the clutch pack sends 30% of torque to the front wheels, giving the Huracan a strong rear-wheel-drive character. If the rear wheels slip, as much as 50% of the power can go the front wheels. And in the right conditions, all the power can go to the rear wheels, where their traction is enhanced by a mechanical locking differential.
The transmission’s shift paddles are larger than is typical, and the typical control stalks have been completely eliminated, with functions like wipers and turn signals relocated to the steering wheel.
The idea, said Reggiani, is to clear the space of everything but steering and shifting controls. Similarly, the instrument panel is a 12.3-in thin film transistor (TFT) display that provides driver-selectable information directly ahead of the steering wheel. Virtual analog instruments are a popular selection for sports cars like the Huracan, but the same display can also show navigation and infotainment information, eliminating the need for a costly, "unsightly" display in the center of the dashboard.
Volkswagen Group's Audi brand showed a new TT coupe employing a similar design philosophy, but while both cars use an instrument display of the same size to eliminate the center display, the two are completely different devices, with different hardware and software, according to Reggiani.
Lamborghini’s system has a resolution of 1440 x 540 pixels, refreshed at 60 Hz by a Tegra 30 graphics processor from Nvidia’s Tegra 3 Series. This speed ensures a smooth sweep of fast-moving virtual analog pointer needles. Simulated tach needles in quick-revving engines have been jerky in their motion in many early examples of LCD instrument panels.
Even when navigation or infotainment information fills much of the screen, important vehicle information remains visible along the lower edge.
The driver’s interaction with the car is also influenced by the Huracan’s optional variable rate steering. The ratio can vary between a racy 9:1 at city speeds and a stable 17:1 at the high speeds that come so easily to the car.
The system can also reduce oversteer and understeer by applying “tiny, targeted countersteering impulses,” according to the company.
Another active technology on the Huracan is the use of magnetorheological dampers that adjust damping rates on the fly according conditions and the driver’s selection of a drive mode.
The Huracan offers three drive modes: Strada, Sport, and Corsa. These modes adjust the engine’s throttle response, muffler by-pass valves, the transmission’s shift characteristics, the all-wheel-drive system, the stability control, the steering system and the adjustable shocks.
Providing critical data needed for all these systems to work their best is a new three-gyro sensor, reported Reggiani. This Piattaforma Inerziale sensor platform directly measures the car’s movement in three axes using three gyroscopes and three accelerometers mounted at the car’s center of gravity. This aerospace-type sensor provides real-time data to the other systems on the CAN (Controller Area Network) bus for faster response.
It is the first time such a system has been used in a mass-produced car, according to Reggiani, though he said he thinks competitors will soon embrace it for its advantages over a conventional system, which uses a single gyro and three accelerometers to calculate movements.
“We dreamed to have this system,” enthused Reggiani. “The more a car is faster, the more you need quick reactions,” he explained. “This system can be so smart, it can do what is necessary before the driver can react.”
But competitors will react, he predicted. “I expect from next year on we will see other cars in the super sport segment using this,” he said.
Of course, such systems need a solid platform from which they can operate, and the Huracan’s hybrid aluminum-carbon fiber unibody is 50% stiffer and 10% lighter than the all-aluminum tub on the Gallardo, said Reggiani.
He declined to provide the actual stiffness specifications, but the company reports the car’s body shell weighs less than 200 kg (440 lb). Lamborghini uses aluminum components with large elements of carbon-fiber-reinforced polymer. So the front and rear sections with the axle mounts are aluminum, while the floor, sills, center tunnel, rear bulkhead, and B-pillars are carbon fiber.
Careful attention to detail see the carbon’s fibers laid out to provide strength in the needed direction, so the rear bulkhead is strongest in the direction of load travel in the event of a side impact, for example.
The difficult part, reported Reggiani, is mating the two disparate materials. “The junction is between an isotropic and non-isotropic material,” he said, “but it must work like a continuous material.”
They achieved this using a combination of stainless steel rivets, glue, and seals that protect the contact points of different materials from corrosion.
The Huracan’s impressive specifications and styling that, from the rear at least, recalled the convex styling of the 1970s Lamborghini Urraco must have impressed prospective customers because the company reported taking orders for more than a thousand of the cars since it began accepting them two months earlier.Continue reading »