Basics of Conversion
There are 2 main types of LPG system being fitted in the market today. These are LPG injection, sometimes refered to as 3rd and 4th generation LPG systems, and venturi/mixer systems which are sometimes referred to as 1st generation LPG systems.
First and second generation LPG systems use venturis or mixers to introduce the LPG to the engine and have been around for a long time and have served the LPG industry well, though there are several benefits gained by using an injection system.
First generation LPG systems have open loop (manually set) fuel control, while second generation systems add electronic control to the system and use feedback from an exhaust oxygen sensor to adjust fuelling.
There are 2 types of LPG injection systems, vapour LPG injection (third generation LPG systems) and liquid LPG injection (fourth generation LPG systems). As the names suggest, the LPG is injected into the engine in its gaseous form in vapour injection and in its liquid form in liquid injection.