[pgfpro]

From some experimenting that I have done on my Talon, lean burn defiantly helps with pumping losses but as others have said it does slow flame speed. I can run lean burn and EGR hot or cold and it gets to a point where flame speed has the final say. I'm now working on my eight proto type lean burn pre-chamber(stratified charge). This new pre-chamber I hope will increase flame speed by a hotter kernel that will reach deeper into the combustion chamber.
Then I should be able to run normal ignition advance with a fast flame speed.