Food for thought....
My 2004 chevy 2500HD gets 13.4 mpg on a good day.
This is the "latest greatest smog-friendly engine" with all the cat converters, smog pumps. etc.
Im getting AWEFUL gas milage. I wonder what it would get if you stripped all the emmission B.S. from it at let it RUN! Im Guessing double mpgs....... wouldn't that be 1/2 emissions?????
BTW it is an awesome motor!