Originally posted by Vandy420a
P.S. is the 3 bucks (max) you saved on 4.5 gallons of 89 worth the potential of melting rings, detonation, or anythign else like that? And no, premium gas has NOTHING to do with gas milage, unless you're using the wrong grade, getting detonation and your ECU is doing weird stuff with timing. THe only way it could possibly help, and this is a really big stretch, is you put it in a car that you had previously been using the wrong gas AND reset the ECU somehow, then noticed a slight power increase and compensated by using less throttle. CAUTION: LONG (duh) BUT BASIC STUFF ABOUT OCTANE--skip to summary if you don't wanna read Gasoline is made up of 6 and 8 carbon chains, called hexane and octane respectively. Hexane is highly prone to detonation under pressure and heat, while octane is much more resistant. However, gasoline needs to be more highly refined to get octane over hexane without adding lead as a stabilizer, artificially boosting the "octane". When people say the word "octane" they are actually not using the word correctly. They (and gas stations) are referring to an average of detonation tests done with a single piston running motor and somethign else, can't remember, not important. They are estimating the percentage of octane versus hexane in a given quantity of gas(89 = 89% octane). This is misleading, because many companies use additives that may highly resist heat detonation and give a "score" of 100+ "octane", which isn't possible, but the gasoline may be volatile under pressure because of the higher quantities of hexane. Its just an average, and its not even that accurate, which is scary enough and is also a reason to buy decent gas. SUMMARY: "Octane" is supposed to mean how many 8 carbon chains but really means resistance to detonation...but most companies don't tell you which kind of detonation, whether its heat induced or pressure induced. 87 and 93 gas contains the same amount of energy. Whats also gonna really blow your mind is that ALL gasoline for a given area is the same stuff, only the additives are different. The Cont. U.S. only has like 3 pipelines total...so the shell and exxon on the corner are really only selling you their additives.