But only if it is cooled before re-introduction into the combustion chamber.

The thing with NOx is that you need HC and NOx and sunlight before it becomes a real problem. NOx by itself isn't a really big deal. Your engine isn't making enough to cause a problem up there in the great white north.

Down here in Kalipornia, NOx and HC combined with all that sunshine really does cause problems. It makes smog, and lots of it.

The problem here is that the cars are getting a bum rap on the deal. It's really industry making most of that crap and they get a pass on it. <img src="/forums/images/graemlins/rolleyes.gif" alt="" />