Before lower-grade gas pumps can be used again, companies like Tank Cleaning Industrial will have to clean them out.

Back in 2004, several automakers got together to create a more pure form of gasoline to meet strict standards set by the U.S. Environmental Protection Agency (EPA), now known as Top Tier gasoline.

Once on the road a street rod's gas tank is one of those parts seldom thought about until it's time to pay for filling it up. But when a car is under construction it's a good idea to give the gas tank ...