The variable intake system, which essentially alters the geometry of the intake system upstream of the primary intake passages, provides three different operating modes obtained by the opening and closing of two butterfly valves (one on the plenum chamber and one on the by-pass pipe), the operation of which is entrusted to the Lamborghini LIE engine control units.

The VACS ("Variable Air-flow Cooling System") is an entirely new concept in air intake technology. A high-performance car obviously requires a high-power engine. And, in turn, a high-power engine needs an efficient cooling system with appropriately proportioned air intakes. In a conventional fixed system, these air intakes have to be dimensioned to suit the most extreme operating conditions, such as, for example, very high external air temperatures, even though these conditions are rarely encountered during normal running (accounting on average for only 15% of the vehicle's total usage). This means that air intakes have to be made too large for average use, thus compromising the car's aerodynamic characteristics and performance.

To avoid this compromise, Automobili Lamborghini S.p.A. has designed a variable air-flow cooling system in which the aperture of the air intakes can be altered to suit the cooling requirements of the engine and the external air temperature. As a consequence, the car's aerodynamic characteristics are only compromised when necessary, which, as stated previously, amounts to only about 15% of the total vehicle usage.

The essential characteristics of the system are as follows:

- The system comprises two rear lateral air intakes that pivot to assume two positions: closed (O deg.) or open (20 deg.). The change from one position to the other can be controlled either automatically on the basis of the operating conditions (engine coolant temperature and external air temperature) or manually, by the driver pressing a button (only with the engine running).

- The opening and closing of the air intakes is controlled by a dedicated PMC electronic control unit, the same unit that controls the movement of the rear spoiler. Should the movement of the air intakes be obstructed, a safety system alerts the driver by way of a warning light.



The Electronics

The management and control of all the engine and vehicle operating parameters is entrusted to a system comprised of 3 "master" control units and 1 satellite control unit, made up as follows: 2 Lamborghini LIE engine management units, 1 Lamborghini GFA auxiliary function management unit and 1 Lamborghini PMC ("Power Motor Control) satellite control unit. All these electronic control units are interconnected by way of a CAN BUS.

More precisely, each of the 2 LIE units (with 32 bit/20Mhz microprocessors) controls one of the two banks of cylinders, each LIE being equipped with an identification pin for the purposes of unit recognition and function differentiation, whereas "body" control functions are managed by the GFA and PMC units, each with a 32 bit/20MhZ microprocessor and 80-pin connector.

The main functions of the electronic control system are:

- Fuel injection management (multipoint injection, timed sequential)
- Ignition management (breakerless ignition with one coil per cylinder)
- Variable valve timing management- inlet and exhaust valves- (VVT)
- Management of the variable-geometry intake system (VIS)
- Detonation management (by knocking sensors)
- External noise level management (Lamborghini ECS)
- Management of the Drive-by-Wire system (electronic throttle)
- Management of the "Traction Control System" (TCS)
- Instrument panel management
- Management of the variable-geometry air intake system (Lamborghini VACS)
- Rear spoiler management

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