Sector: LPG

LiquidSi by Vialle - already available

The greatest obstacle hindering the popularisation of liquid state autogas injection systems, at least in some cost-sensitive markets, has always been their price. Now, thanks to a new approach adopted by a Dutch pioneer of 5th generation systems, tables are about to turn.
LiquidSi by Vialle - ECU module with LPG/petrol switch© VialleTypically for Vialle systems, the LiquidSi has a module structure

Let's start from the very beginning. The first liquid state injection system was the LPi, whose dedicated nature, together with the necessity of shipping intake manifolds to Vialle's headquarters to have them precisely perforated for LPG injectors to be mounted, made the entire conversion process complex, time-consuming and costly. Introducing the LPdi and LPfi was the next chapter. While the former is also a dedicated solution (albeit designed for converting direct-injected engines, using OEM high-pressure fuel pump and petrol injectors in the process), the latter is the first major step towards making a versatile 5th generation system, one that can incorporate certain components from suppliers other than Vialle.

The LiquidSi (liquid smart injection) is a development of the original LPfi, pushing versatility and conversion process simplicity even further. First of all, the system has a single version for all engines with 3 to 8 cylinders. Moreover, connecting the ECU (itself featuring advanced autoadaptation and injection map correction tools) to the car's electrical system requires only as few as 4 soldered wire connections – all others are made with „quick” connectors. As for the LPG tank and pump mounted on it, certain simplifications have been made, too. Any standard autogas tank may now be used, while up to now special, custom containers capable of housing pumps were required. The pumps as such now feature warranty over 100 thousand km of mileage.

5th generation autogas systems are universally believed to do well without valve seat lubrication additives, since vapourising LPG directly into the intake manifold is by its nature a sufficient means of decreasing engine temperature in the cylinder head area. What's more, complex hydrocarbon fractions contained in autogas – which would deposit as heavy oil in the reducers and injectors of vapour state injection systems – are injected into combustion chambers with the fuel and burn to form protective compounds accumulating on valves and seats. The additional intercooler effect (cooling of air entering the engine from LPG vapourising in the manifold and absorbing heat from its surroundings) is also a typical feature of 5th generation systems, including the LiquidSi.

Since conversion cost is an important – even crucial – factor when it comes to the LiquidSi, let's now have a closer look at it. According to LTA Polonia, a Polish distributor of Vialle products, the LiquidSi should have a final price tag of 4500 zlotys (approx. 1100 euros), which doesn't exactly allow it to combat popular Polish-made 4th generation systems, but could make the newcomer competitive compared to Italian autogas systems, particularly those used for converting engines requiring extra lubricating additives and lubricant application systems. The LiquidSi is already available in select markets.


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Robert Markowski
source: LTA Polonia, Vialle 2012-2018 All rights reserved. By using this site you acknowledge that you accept its Terms and Conditions