Unleaded 98 Gasoline is particularly suitable for use in high-compression gasoline engines. (Some older engines require leaded gasoline.)

Typical values: Density kg/m3 0.735, Gross calorific value 11300 kcal/kg. Unleaded 98 does not contain bioethanol.

In a gasoline engine, you do not want the gasoline to self-ignite. The octane rating indicates the gasoline's ability to resist such self-ignition, and is therefore an important quality parameter. Octane rating is measured, among other things, using RON (Research Octane Number). 95-octane gasoline sold in Norway means it has an octane rating of 95 RON. For 98-octane, the octane rating is therefore 98 RON. If an engine is run on gasoline with too low an octane rating, the gasoline vapor in the combustion chamber can self-ignite from the heat of compression instead of from the spark from the spark plug. This is called engine knocking or pinging.

A common misconception is that the octane rating in gasoline says something about the amount of energy in the fuel or that the engine delivers more power the higher the octane rating used. The truth is that gasoline has the same amount of energy regardless of the octane rating.