Quote:
Originally Posted by serialk11r
...while lean burn can add substantial efficiency.
|
True. Most all gasoline engine vehicles try to run at stoichiometric for the most part, which isn't ideal. Of course an obvious disadvantage is the greater NOx emissions.
The question is how lean? Lean helps burn up all the fuel. It also reduces throttling losses like EGR, but burns up more fuel. But the leaner you go the slower the flame, which hurts efficiency. You can counteract that to a degree by advancing the timing.
This is why a stratified charge would be ideal. Or maybe multiple sparkplugs.