> frank dadog Wrote:
You actually get different
> concentrations of byproducts based on the stoichiometric ratio which
> dilute the charge, nitrogen being the key one.
Just to clarify this, in looking at combustion physics it seems that the oxidation of carbon at near stoichiometric ratios, the burn rate is more heavily influenced by the production of CO2 and CO molecules by the flame front as it propagates. There are 3 reactions C+O2, CO+CO2 and CO+O2. When the reaction favours CO the burn rate increases, when the reaction favours CO2 the burn rate decreases. In a lean mix the nitrogen bonds with excess oxygen to form NOx and slows down the reaction. Nitrogen is more peripheral to the rate of burn than an active participant. FWIW.