I hesitate to drag this out, but octane number, volatility and energy content are independent properties of the components and any blend of motor fuel. Volatility may be expressed as vapor pressure. Refiners raise vapor pressure in the winter to assist cold-weather starting and reduce it in the summer to prevent vapor lock. Users never know what they are getting at the pump, especially in the swing season as the refiners change their blends. When ethanol is blended with gasoline, the overall volatility is managed by the refiners to a specific target. When the mix is introduced into the intake system by a carburetor or a fuel injector, it is appropriate for the liquid fuel mix to be finely atomized so that it does vaporize once it is in the hot combustion chamber. The energy of the components, including ethanol, is then released in the combustion process, producing the downward pressure on the top of the piston. The finer the atomization, the quicker the vaporization and the more likely complete combustion will occur. Combustion pressure produces force on the piston, resulting in torque on the crankshaft, management of the torque in a TorqueFlite, distribution of the torque to the axles, wheels and tires and fun-fun-fun in our 300's! BTW, my rough calculations show ethanol contains about 50% oxygen and 4% water by weight. And that stuff is still free. The liquid oxygen is released for combustion in the engine and does help many engines produce cleaner exhaust, but I question its true energy value. Its political, geo-political and environmental values are harder to calculate. C-300'ly, Rich Barber Brentwood, CA -----Original Message----- From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On Behalf Of News4ge@xxxxxxx Sent: Tuesday, August 21, 2007 5:44 PM To: awrdoc@xxxxxxxxx; hurst300@xxxxxxxxxxx Cc: hurst300@xxxxxxxxxxxx; Chrysler300@xxxxxxxxxxxxxxx Subject: Re: [Chrysler300] Drivability Problems Related To Ethanol? Can somebody clear something up? If ethanol is more volatile than gas, wouldn't that mean that it lowers the octane? Doesn't high octane mean less volatility ( therefore less inclined to ping/ pre-ignite)? Or do I have this backward? George Clineman ************************************** Get a sneak peek of the all-new AOL at http://discover.aol.com/memed/aolcom30tour [Non-text portions of this message have been removed] To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/ Yahoo! Groups Links To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: mailto:Chrysler300-digest@xxxxxxxxxxxxxxx mailto:Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/