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Old 09-10-2011, 03:19 PM   #13
landrovered
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Join Date: Nov 2009
Location: Madison, Georgia
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Sure ethanol increases octane just like JP-5 but that was my point...it is not the octane additive that you are getting when you pay extra for 92 unleaded. That increase comes from isooctane and toluene.

I did say near stochiometric, I know that many engine manufacturers run their fuel curves very rich to cool the fuel/air mixture to reduce knocking and also to insure complete combustion in the catalytic converter but that really just reduces overall efficiency and of course too lean under load makes for hot spots and can cause cracked heads and all sorts of other problems. It is a Goldilocks deal.
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