Many drivers still remember pulling up to the fuel pump and having to choose between leaded and unleaded gasoline. Vehicles built between the 1920s and 1970s ran on leaded fuel which helped protect a car’s soft valve seals. Unfortunately, what was good for a car was not healthy for the environment or driver. The leaded gasoline fumes spewing from the exhausts of millions of cars were deemed unsafe and, as a result, leaded gas was eventually phased out. When you pull in to fill up your tank, three large numbers display your choices: usually 87, 89 and 92. What do they mean? Octane ratings actually range from 87 (regular) to 94 (premium). The rating is the measure of a fuel’s