Date: Mon, 1 Mar 1999 16:14:08 -0500 From: "Mike Smith" <kld_msmithnopsamAMearthlink.net> Subject: Re: Can someone explain OCTANE?
Justin VanAbrahams wrote in message <36DA82F3.407nopsam.com>... >GK wrote: >> >> Can someone please explain exactly what octane is and how it effects an >> engine? > >Let me first establish I am not a scientist. I might not know >what I'm talking about. If that's the case, anyone out there is >free to correct me... :) Uh... OK, then. ;-) >Octane is a chemical present in fuel which resists ignition. >In gasoline, it's primary function is the prevent the mixture from >burning abnormally, which can happen when the gas reaches a >temperature (or a pressure) when it actually ignites itself. Bzzt. Octane *might* exist in various amounts in gasoline as a by-product of the manufacturing process, but it is not a primary ingredient. Octane, C8H18, is a hydrocarbon that exhibits properties similar to gasoline, particularly that is is combustible (duh) and that it exhibits a flash point (temperature at which spontaneous combustion takes place, which is what causes knock) of around 800 degrees. Because it has properties that are similar to those of gasoline, and it is a repeatably reproducible substance of an exact, known formula, it makes a good "benchmark" against which to compare real gasoline, which is actually a mix of many different hydrocarbons. (Plus other substances like detergents and oxygenators like MTBE). -- Mike Smith. No, the other one.