| Abstract |
Data obtained by General Motors Corporation in three fuel economy surveys of 1975 GM private passenger car owners are analyzed to determine seasonal, topographical, and geographical effects on the fuel economy of in-use vehicles. Data from the GM survey for 1532 cars formed the basis for this study. Additional seasonal, topographical, and geographical data associated with the locations of the owners were acquired from the literature and added to the GM data base. Carline classes are defined that contain cars with the following parameters in common: GM Division, Inertia Weight, CID-BBL, Transmission Type, and Axle Ratio. Within each carline class, harmonic mean fuel economics are computed for groups of cars with extreme ranges in each of eight seasonal, topographical, and geographical parameters. The dependence of fuel economy on these parameters is determined by comparing fuel economics between groups. Sales weighted harmonic mean fuel economies are computed for analogous groups at the division and fleet level. (Portions of this document are not fully legible) |
