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Petrol and LP Gass (home gas) Engine Answered

Hi, I am in South Africa and recently had a conversation with someone who tells me that one of our security companies runs their cars on a mixture of normal petrol(gasoline)and house gass as a test to get cheaper mileage.Does anyone know how this can be done?


It's an idea I have played with, but never successfully on a carb'd engine. The main problem that I have had is delivering the propane to the cylinder. A retrofit of a mixed-fuel system onto an engine designed for petrol only is rather involved. However, using ONLY propane is relatively easy. If you are using a fuel-injected car, instead of one with a carburettor, the main concern is connecting your propane supply to your existing fuel injection system. You will need to wrap your tank with something to actively warm it (an electric blanket comes to mind) to maintain a steady gas pressure. Otherwise, your car will draw propane fast enough that ice will form on the tank, the LP will get really cold, and the pressure will drop. Using LP in a fuel-injected application involves adjusting your fuel/air mix for optimum power. Sometimes running with the petrol adjustment works okay, but on other engines it won't work at all. If you can't remap the injection profile easily, simply adjusting the amount of air available does wonders. If you've got a lean condition, putting on a more restrictive air filter or partially blocking your air intake can fix that. A rich condition can often be fixed by simply putting on a higher-flow filter, or relocating the intake so it's pulling colder air.

Hi after reading your post I am interested in contacting someone who can do such a conversion ...or...if it is not too complicated where can i buy a 'kit' & do it myself Thanks Monty