Mobil Economy Run

It was designed to provide real fuel efficiency numbers during a coast-to-coast test on public roads and with regular traffic and weather conditions.

The Mobil Oil Corporation sponsored it and the United States Auto Club (USAC) sanctioned and operated the run.

This was rather different from the current method of computing fuel consumption by the United States Environmental Protection Agency (EPA) by running cars on chassis dynamometer in a climate-controlled environment.

To prevent special preparation or modifications to the participating automobiles for the run, the United States Auto Club purchased the cars at dealerships, checked them and, if certified as "stock", their hoods and chassis were sealed.

Because of the many types of automobiles, the Mobil Economy Run had eight classes based on wheelbase, engine and body size, as well as price.

The leading automakers provided drivers and in each car was a USAC observer to prevent any deviations and penalize for traffic or speed limit violations.

However, starting in 1959, entries were judged on an actual miles-per-gallon basis, instead of the ton-mileage formula used previously which favored bigger, heavier cars.

[3] An example was to use lightweight motor oil during the allowable 1,500-mile (2,400 km) "break-in" period "to promote faster wear and loosen the engines up quickly.