The Lamborghini Sián Roadster, unveiled in July 2020 and produced through March 2022, represents the open-top iteration of Lamborghini’s first foray into a production hybrid supercar. Built on the foundations of the Aventador, the Sián Roadster (and its coupe sibling) showcased Lamborghini’s commitment to blending extreme performance with innovative hybrid technology. Limited to just 63 units, the Roadster is a highly exclusive vehicle positioned at the very pinnacle of Lamborghini’s model range, offering a unique and dramatic driving experience. It utilizes a mild-hybrid system to augment the naturally aspirated V12 engine, delivering a combined output of 819 horsepower.
Technical Specifications
| Brand | Lamborghini |
| Model | Sián |
| Generation | Sián Roadster |
| Type | 6.5 V12 (819 Hp) Hybrid AWD ISR |
| Start of production | July, 2020 |
| End of production | March, 2022 |
| Powertrain Architecture | MHEV (Mild Hybrid Electric Vehicle) |
| Body type | Roadster |
| Seats | 2 |
| Doors | 2 |
| Combined fuel consumption (WLTP) | 18.5 l/100 km (12.7 US mpg, 15.3 UK mpg, 5.4 km/l) |
| CO2 emissions (WLTP) | 447 g/km |
| Fuel Type | Petrol (Gasoline) |
| Maximum speed | 350 km/h (217.48 mph) |
| Emission standard | Euro 6 – LEV 3 |
| Weight-to-power ratio | 2 kg/Hp, 497.9 Hp/tonne |
| Weight-to-torque ratio | 2.3 kg/Nm, 437.7 Nm/tonne |
| Battery voltage | 48 V |
| Battery technology | Lithium-ion (Li-Ion) |
| Electric motor power | 34 Hp |
| Electric motor Torque | 35 Nm (25.81 lb.-ft.) |
| Electric motor location | Integrated into the transmission |
| System power | 819 Hp |
| Engine Power | 785 Hp @ 8500 rpm |
| Power per litre | 120.8 Hp/l |
| Torque | 720 Nm @ 6750 rpm (531.04 lb.-ft. @ 6750 rpm) |
| Engine layout | Rear, Longitudinal |
| Engine Model/Code | L539 |
| Engine displacement | 6498 cm3 (396.53 cu. in.) |
| Number of cylinders | 12 |
| Engine configuration | V-engine |
| Cylinder Bore | 95 mm (3.74 in.) |
| Piston Stroke | 76.4 mm (3.01 in.) |
| Compression ratio | 11.8:1 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Engine oil capacity | 13 l (13.74 US qt | 11.44 UK qt) |
| Coolant capacity | 25 l (26.42 US qt | 22 UK qt) |
| Kerb Weight | 1645 kg (3626.6 lbs.) |
| Length | 4979 mm (196.02 in.) |
| Width | 2080 mm (81.89 in.) |
| Width including mirrors | 2265 mm (89.17 in.) |
| Height | 1158 mm (45.59 in.) |
| Wheelbase | 2700 mm (106.3 in.) |
| Drivetrain Architecture | All wheel drive (4×4). ICE and electric motor drive rear wheels, with front wheel drive capability via clutch. |
| Number of gears | 7 |
| Gearbox type | Automatic transmission ISR |
| Front suspension | Double wishbone |
| Rear suspension | Double wishbone |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Steering type | Steering rack and pinion |
| Power steering | Electric |
| Front tires | 255/30 ZR20 92Y |
| Rear tires | 355/25 ZR21 107Y |
| Front wheel rims | 9J x 20 H2 |
| Rear wheel rims | 13J x 21 H2 |
INTRODUCTION
The Lamborghini Sián Roadster is a limited-production, two-seat, all-wheel-drive hybrid sports car produced by the Italian manufacturer Lamborghini. Unveiled in July 2020, it builds upon the Sián coupe, introducing an open-top experience without compromising the groundbreaking hybrid powertrain. The “Sián” name, meaning “flash of lightning” in Bolognese dialect, reflects the car’s rapid acceleration and innovative technology. The Roadster is based on the Aventador platform, but features significant modifications to accommodate the 48-volt mild-hybrid system and unique styling cues. Only 63 examples were produced, making it one of the most exclusive Lamborghinis ever created.
Powertrain & Engine Architecture
At the heart of the Sián Roadster lies a naturally aspirated 6.5-liter V12 engine, designated the L539. This engine produces 785 horsepower at a screaming 8,500 rpm and 531 lb-ft of torque at 6,750 rpm. The engine utilizes a multi-port fuel injection system and a high 11.8:1 compression ratio to maximize power and efficiency. What sets the Sián apart is the addition of a 48-volt mild-hybrid system. This system incorporates a 34-horsepower electric motor integrated directly into the gearbox. The electric motor isn’t used for all-electric driving; instead, it provides a power boost during acceleration and assists with low-speed maneuvers. A supercapacitor, rather than a traditional lithium-ion battery, stores the energy recovered during braking. This allows for faster charging and discharging, delivering an immediate power boost when needed. The transmission is a 7-speed Independent Shifting Rod (ISR) automated manual gearbox, optimized for rapid gear changes.
Driving Characteristics
The Sián Roadster delivers a truly exhilarating driving experience. The combination of the naturally aspirated V12 and the electric motor results in a combined output of 819 horsepower. This allows for a 0-62 mph (0-100 km/h) sprint in under 2.9 seconds and a top speed of 217 mph (350 km/h). The 48-volt system provides instant torque fill during acceleration, eliminating any hint of turbo lag. The ISR transmission shifts quickly and decisively, contributing to the car’s overall responsiveness. Compared to a standard Aventador, the Sián Roadster feels significantly more potent, particularly during acceleration. While the Aventador relies solely on the V12 for power, the Sián’s electric motor provides an extra layer of performance. The all-wheel-drive system ensures excellent traction, even in challenging conditions.
Equipment & Trim Levels
Given its exclusivity, the Sián Roadster offered a high degree of customization. Standard features included a bespoke interior with extensive use of Alcantara and leather, a fully digital instrument cluster, and a sophisticated infotainment system. Each Sián Roadster was essentially tailored to the owner’s preferences, with a wide range of exterior colors and interior finishes available. Optional extras included carbon fiber trim, upgraded audio systems, and personalized embroidery. The Roadster’s design incorporated unique aerodynamic elements, including a retractable rear spoiler and active cooling vents, to optimize performance and stability.
Chassis & Braking
The Sián Roadster’s chassis is based on the Aventador’s monocoque construction, utilizing extensive carbon fiber to minimize weight and maximize rigidity. The suspension features double wishbones at both the front and rear, with magnetorheological dampers to provide adaptive damping control. The braking system consists of ventilated discs at all four corners, with six-piston calipers at the front and four-piston calipers at the rear. ABS (Anti-lock Braking System) is standard, ensuring optimal braking performance in all conditions. The Roadster’s weight distribution is carefully balanced to enhance handling and stability.
Market Reception & Comparison
The Lamborghini Sián Roadster was met with widespread acclaim from automotive critics. Reviewers praised its stunning design, exhilarating performance, and innovative hybrid technology. The Sián was seen as a bold step forward for Lamborghini, demonstrating the company’s commitment to electrification while preserving the visceral experience of a naturally aspirated V12. Compared to the Aventador, the Sián Roadster offered a significant performance upgrade, thanks to the added electric motor. While the Aventador focused on raw power and driver engagement, the Sián provided a more refined and technologically advanced driving experience. Fuel economy, unsurprisingly, was not a primary concern for Sián buyers, with the car returning approximately 12.7 US mpg.
Legacy
The Lamborghini Sián Roadster represents a pivotal moment in Lamborghini’s history, marking the brand’s first foray into hybrid supercar production. The Sián’s innovative technology and striking design have paved the way for future Lamborghini models. On the used car market, the Sián Roadster commands a substantial premium, reflecting its rarity and exclusivity. The L539 engine, while complex, has proven to be relatively reliable, and the mild-hybrid system has not presented any major issues. The Sián Roadster is destined to become a highly sought-after collector’s item, representing a unique and significant chapter in Lamborghini’s storied legacy.
