Kevin Cameron from cycle world magazine is a really smart feller when it comes to engines and all things mechanical. He did an article about these 100 miles to the gallon things and was able to prove to me why they can't work. There is only so many btu's in a gallon of gasoline, even if you could get 100% efficiency turning that gallon of fuel into motive energy, you'd still be no where near 100mpg in anything resembling an automobile. From my own point of view, if it was a easy as cutting some grooves somewhere, why wouldn't the auto companies do that instead of spending millions of R&D dollars developing hybrids and cylinder de-activation and 27 speed transmissions?