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Old 02-12-2015, 08:09 PM   #26 (permalink)
2000mc
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Quote:
Originally Posted by stovie View Post
may I ask how inefficient running lean would make the catalytic converter??
I think they can't reduce nox if they stay lean very long, I think the 14.7:1 matters more to the cat than the engine

Stolen from Catalytic Converters - Chemwiki
There are two types of "systems" running in a catalytic converter, "lean" and "rich." When the system is running "lean," there is more oxygen than required, and the reactions therefore favor the oxidation of carbon monoxide and hydrocarbons (at the expense of the reduction of nitrogen oxides). On the contrary, when the system is running "rich," there is more fuel than needed, and the reactions favor the reduction of nitrogen oxides into elemental nitrogen and oxygen (at the expense of the two oxidation reactions).
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