LPG SUPPLY SYSTEM FOR ENGINES WITH POSITIVE IGNITION AND METHOD FOR ESTIMATING THE COMPOSITION OF LPG IN SAID SYSTEM

A method (100) for estimating the composition of LPG in an LPG supply system (1) for engines with positive ignition, the LPG supply system (1) comprising an LPG tank (2), a pressure reducer (3), a first conduit (HP) that extends between the tank (2) and the pressure reducer (3), a plurality of injectors (4) and a second conduit (LP) that extends between the pressure reducer (3) and the injectors (4), the method (100) comprising the steps of: - recognising an incipient condensation condition of the LPG (101), which takes place when the LPG in vapour form starts to pass into liquid form; - in response to the recognition of the incipient condensation condition of the LPG, detecting first LPG injection pressure and temperature values (102); - starting from the first LPG injection pressure and temperature values detected, obtaining a corresponding percentage of propane and/or butane contained in the LPG (103).