I was getting better than 30 miles per gallon in both my American Motors Hornet, and Gremlen back in the early 70's. Then the government required extensive antipollution remedies. This did decrerase the mount of smog per gallon, but also decreased the amount of Miles. Instead of putting bandaids on bandaids that result in minimal improvements, we need to change the paradigm onece again and go to alternate means of operating vehicles. And yes the technology is there. The electric sportscar company in California is producing an electric car with a 200 mile range and batteries that charge from household current and can be recharged up to 500 times before the charge capacity starts to decline. Thats over 100,000 miles.