Greetings . . .

Super premium pump gas can still be had at select locations:
Sunoco 260 GT Locations now rated to 100 octane.

Back in the day Sunoco 260 also contained Tetra-Ethyl Lead - which took it up to 110 octane. As if that wasn't enough - some of the motor heads at my high school would go to the air-field with Gerry cans to get 120 octane av-gas . . .

Never heard the story that Sunoco had more than a 260 grade in the under ground tanks. My understanding was that they delivered a boat load of 190 grade and a smaller percentage of 260 grade and then intermixed the two at the pump to get any grade in between: 200, 220, 240 - which today correspond to 87, 89, 91 on their pumps - again with only 86 and 94 octane in underground storage.

regards,
stock49

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