[Slow Lane]

As I understand it, any more than 10% ethanol in U.S. cars
would ruin the engine. There are some cars that can switch
from gas to alcohol, but the majority cannot.

[radioman]

As I understand it, any more than 10% ethanol in U.S. cars would ruin the engine.

Alcohol will not ruin the engine. In fact, alcohol will extend the life of your engine. Some fuel pump diaphrams will deteriiorate with alcohol. This is a minor, easily solved problem. You can switch to run straight alcohol cheaply with off the shelf parts.
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