Dennis Haynes wrote:
>
> Any vehicle equipped with an O2 sensor is also equipped with a 3-way Cat.
> The Vanagon uses this set up to eliminate the need for an EGR valve.  Lean
> mixtures and high compression increase peak flame temperatures.  This
> increases the production of NOx.  Over advance timing also contributes to
> NOx.
>

Just wanted to add that the over-advance of the timing causes early
expansion of the combustion gasses that gets compressed and causes
higher peak pressures and temps; it also kills net power.

--
Best Regards,
Scot Douglas
Project Engineer; Chrysler/Mitsubishi Joint Programs
Mitsubishi Motors R&D of America
P: (313) 971-0900 x32
F: (313) 971-0901