I am old school. We had guys back in the 60's and 70's building carburetors and tuning with cars reaching 70mpg. Their work was quickly bought out. Who do you suppose bought the patents and copyrights? We use to ticker a bit with mileage, but it always hurt performance. There's no reason today with computer technology and the ability to right programs, and monitor the performance parameters of an engine, it can't be done. Someone in the industry has that answer.