The objective was the coveted title as the Mobilgas Economy Run winner in each class. 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.
The objective was to secure the coveted title of Mobilgas Economy Run champion in each category. However, beginning in 1959, competitors were evaluated based on their real-world fuel efficiency, rather than the ton-mileage formula used earlier, which gave an advantage to bigger and heavier cars.