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ThatVietGuy - SolaraGuy Semi-Pro Racer
- Posts: 2507
- Joined: Sat Jun 25, 2005 1:50 am
- Location: SoCal
The octane rating refers to the amount of cyclic octane molecules in the fuel. Translation: Higher number = more ring type octane molecules. Octane is an 8 carbon molecule, and it can be in a straight chain or in a ring so that every carbon is connected to two other carbons. Regular straight chain octane is as weak as any other straight chain molecule, but cyclic octane is far stronger under compression. If your engine is running high compression in the combustion chamber then you need a larger percentage of your fuel to be made up of cyclic octane to handle that compression. Most of these Solara engines have low compression numbers, so they can run 87. If you are running the TRD charger, a turbo, or you have had your head decks milled, then you should move up to a higher octane fuel to prevent "pinging," knocks, and possibly detonation. To the point: You won't see any benifit to a much higher octane fuel if you are running low compression numbers (ie 9.5:1).
By the way, I am a chemisrty student at UMass so this isn't a load of cr*p!
Hope this helps,
David