Actually, it's alot less complicated than that... It's called ethanol.... I only buy 100% gas and it last alot longer... I get about 3-4 MPG more with 100% gas than with the mixed crap... It only costs about 10-15 cents more per gallon but you make it back after each fill up... There are only about 4 or 5 gas stations here in Tulsa that still 100% gas... Check out this write up and forum...
TulsaNow Forum - REAL GAS - NO QTrip E10

and a write up in the Tulsa World...read the comments...

http://www.tulsaworld.com/news/artic..._12_OKLAH36326