With the development of our LPdi system Vialle has once again reconfirmed its leading position as manufacturer of alternative fuel and autogas systems. LPdi is a next step development of our LPI system which injects autogas in a liquid phase into the intake system instead of first vaporizing autogas as in done in the more conventional systems. Just as with LPi the LPdi system keeps the autogas in a liquid state throughout the entire process. However, with the LPdi system the intake valves are bypassed which makes its suitable for the newest direct injection engines. The autogas is introduced into the cylinders via the standard gasoline injectors. For this groundbreaking system several new and patented components have been developed.
The LPdi system has several advantages. It is a service friendly system since due to the direct injection no filters require replacing. In addition no changes are made to the engine's cooling system so that the full power of the engine remains available. Direct injection using the environment friendly autogas can also lead to a CO2 reduction of up to 20%. For both new and existing vehicles compliance to the Euro 5 emission standard remains. Direct injection makes it possible to exactly meter the amount of fuel to be injected. This ensures that the engine management system's full capability can be utilized and this ensures optimal fuel consumption and drivability.
LPdi makes use of a tank with an integrated membrane pump well known from LPi. The pump increases the pressure in the system and provides for fuel circulation. The beating heart of the LPdi system is the patented FSU (fuel selection unit) which allows problem free switching between gasoline and autogas. Gasoline and autogas are fed into the FSU and the selected fuel is passed on to the original high pressure pump, in the car, which increases the pressure to more than 100 bar before injection takes place. The system is unique in that the car can also be operated in a mono fuel mode. Also the engine can be started using autogas. The gasoline system than only serves as a back up in case the LPG tank is empty. Of course the driver is free to switch from one fuel to the other should he so choose via the tried and trusted Vialle fuel switch. Autogas has the physical property that under certain circumstances it can vaporize under influence of heat and temperature. This can result in start times which are longer than those you are used to with gasoline engines. In order to minimize this effect, the autogas pump is activated at the moment that the car door is opened on some models in order to achieve earlier build up of pressure in the system. This pressure increase allows any fuel in gaseous form to be recompressed in to liquid.