On the contrary, it works very well in autos designed for it, Race engines love the stuff. High octane, cheaper price when compared to race gas. Supercharged and turbocharged engines love it. Carb needs to be modified to flow more fuel and to withstand the high level of alky. Of course the fuel system has to be upgraded as well. Wish we had a pump here in town. My '70 Monte would be running it. Car Craft, Hot Rod, etc. have had numerous articles on it over the last couple of years.