Lamborghini liberates the Sián Roadster
Lamborghini has released its limited edition, open-top Sián Roadster. The centrepiece of the hybrid hypercar is a V12 engine with unique hybrid technologies, utilising a supercapacitor. Sián in the local Bolognese dialect means ‘flash’ or ‘lightning’.
The roofless design adds to the emotional appeal, the raw V12 sound more intimate with no roof to exclude it.
Sián Roadster mimics the futuristic design of the Sián coupé, in an open-top setting. There are the clear aero aids shown in recent Lambo models, and evidently there is no loss of aerodynamic efficiency from the roadster’s roofless design. The rear wing extends only to enhance the performance. Active cooling vanes react to exhaust temperature. Sián has the distinctive Y-shaped headlights and hexagonal tail lamps of other Lamborghinis.
The Sián Roadster’s hybrid system combines the V12 engine with a 48-volt e-motor delivering 25kW. It is located within the gearbox to provide immediate response and improved performance. The e-motor works alone for parking and reversing.
Lamborghini’s uses a supercapacitor that the firm claims stores ten times the power of a lithium-ion battery. It is sited in the bulkhead between cabin and engine, helping optimise weight distribution. The supercapacitor and e-motor weigh 34 kg, and overall weight-to-power is 1.0 kg/hp (1.34kg/kW).
Combined system power is 602kW and a top speed of over 350km/h is claimed. So is a 0-100 time of 2.9sec.
Regenerative braking fully charges the Sián’s storage system every time the vehicle brakes. So the energy stored is instantly available for boosting power up to 130 km/h when the e-motor automatically disconnects. It is said to be over 10 per cent faster for overtaking as a result.
The hybrid system also improves driving comfort, the e-motor eliminating the interruption of power during gear changes so there is a constant feeling of acceleration, eliminating jerking movements during upshifts.
Stefano Domenicali, Lamborghini’s Chairman and CEO said at its launch “It is the expression of breathtaking design and...embodies important future technologies. The Sián’s innovative hybrid powertrain heralds the direction for Lamborghini super sports cars.”
Only 19 are being made and all are evidently spoken for.