The octane number of a gasoline is a measure of its resistance to detonation. Detonation occurs when the octane number is too low for the engine and its operating conditions. Detonation causes the maximum pressure in the combustion chamber to be reached before the piston reaches top dead center and pushes down the piston before it has reaches the top of its travel. Much of the gasoline's energy is wasted in trying to move the piston up while the high-pressure gasses are trying to push it down. The extreme temperature and pressure developed can cause broken rings, rod-bearing damage, piston overheating, and erosion of the aluminum.
Pistons sometimes end up with holes in their tops from the high temperatures and high pressures.
It is the highest octane street-legal racing fuel available. It contains a complete additive package approved by Environmental Protection Agency and California Air Resource Board that keeps carburetors, fuel injectors, and intake valves clean. 76 Unleaded Racing Gasoline can be blended with motor gasolines with no adverse effects. Use the custom blending chart to economically produce the octane number that your vehicle requires. The number 98 appears in the body of the table in several places, one being where the vertical column indicating six gallons of 100-octane unleaded intersects with the line that indicates two gallons of 92 octane.