Autogas

Cylinder cracks are nothing new, however, and there is no reason to expect autogas-burning engines to have a higher incidence of head cracking than avgas-users.

In the area of autogas volatility, a Reid vapor pressure of 9.0 to 15 is very common, compared to the vapor pressure of avgas, which is 5.5 to 7.

Autogas can be obtained for a fraction of the cost of avgas, but its use is not without controversy.

Petrol ... 20.3% more than autogas ... The results conclusively demonstrate the carbon benefits of autogas vehicles

Autogas powers more than 10 million vehicles in over 54 countries worldwide .... In terms of air-borne emissions of the principal regulated noxious gases, autogas is among the lowest emitters of all ...

Autogas is the common name for liquefied petroleum gas (LPG) when it is used as a fuel in internal combustion engines in vehicles.