What crenwelge said. When I drove transport back in the 70s when you emptied out the tank truck, you might have a gallon or two residual product. Even in a small 500 gallon compartment the contamination is minimal. In terms today octane is misleading. There is no lead in todays gasoline, and the term octane refers to a lead compound used in the additives of earlier formulations of fuel. If my facts are off feel free to correct me.
