[rdass623]

thanks for the replies, it was not an economic question, as much a operational question. thanks jfp, that was the answer I was looking for.

from my experience, some cars' ecu would not pull timing and richen the afr, thus leading to destruction of the engine. the question was just simply to ascertain whether it would be acceptable in an emergency situation.

by the way, living in an area which has the occasional hurricane and mandatory evacuations, sometimes the availability of specific fuels is not an option..