ohh true...sick! hahaha

 

Thank you... Apparently the act of injecting the fuel directly into the combustion event causes a pretty drastic cooling effect due to the rapid evaporation of the liquid fuel mist(IIRC it falls under "latent heat of vaporization"). As I alluded to in my earlier post, diesels inject the fuel in virtually the same manner. It ends up working out like this...

HC and CO emissions = down (These are the two main players in determining combustion efficiency)
NOX and particulate(soot) emissions = up (NOX emissions go up because the same cooling effect allows static AND dynamic compression ratios to be raised in order to get better fuel economy and power... BUT it's a major player in the production of visible smog)

Ya can't win for losing with an internal combustion engine.