Fuel Economy

[why?]

Originally Posted by roxy1

starting in 2004, the EPA started using indolene across the board, a standardized test gasoline free of additives. it has a MON of 87 and RON of 96.5, thus yielding a pump octane of 91.5. before 2004 they used a variety of octanes, depending on what a given car was designed to run on.

using an ethanol free/additive free test gasoline give the best possible mpg numbers. the higher octane itself does squat for mpg numbers.

if I fill up with an ethanol free gasoline I will immediately realize a 7%-10& increase in fuel economy for that tank. my records over the last 15 years also tell me filling up with a higher octane fuel that has ethanol gains me absolutely no measurable fuel efficiency gain over 87 octane.

of course using an ethanol free gas is better. Try finding a station that has that though. I never argued using higher octane would give anyone any gains. I actually know how cars work. Modern cars do not have the ability to adjust enough stock for any higher octane.

Look, the EPA itself doesn't actually do any testing, the manufacturers do. The EPA just writes how the testing has to be done. And we all know the test itself is total bs. IF this was not the case we would not have a rash of automakers being sued over gas mileage figures, we would have a rash of lawsuits involving the EPA, because the test is totally bogus and does not apply to the real world in any way.