What is ec unleaded gas?

EC-Premium is the second gasoline designed and commercially introduced by ARCO to reduce air pollution in Southern California. EC-Premium is designed to be used in cars using unleaded gasoline requiring the performance of a high octane gasoline.

Three standards covered automotive fuel quality: EN /32/EC), to continue to permit the placing on the market of unleaded regular grade petrol

Arco chose to market EC-1 as a replacement for its leaded regular gas, aimed only at owners of older cars and trucks--those without catalytic

Introduced its second less-polluting gasoline Thursday, a premium unleaded it said would burn cleaner and cost less than any competitor's. He said Arco would absorb the extra costs of making the new gas, known as EC (for emission control) Premium, rather than passing them along to dealers in higher wholesale prices.

However, at the gas station, I was confused. There were four options. "What does EC Unleaded 87 mean?" "What's difference these four gases

ARCO's newest fuel will replace the company's Super Unleaded at more but ARCO said EC-Premium burned cleaner because it contained