Results of a study on the relation between gross weight and net engine horsepower of commercial vehicles are presented in this article. Data from the braking performance study were used to update current information on weight power ratios of trucks and to investigate the trend in these ratios since 1949. A total of 1.026 commercial vehicles, in a large variety of types, weights, and horsepower were sampled in three states from routes having a heavy concentration of commercial vehicles. Data from the study were used to determine the effect of weight-power ration requirements on the trucking industry and to determine the percentage of vehicles affected by a minimum performance requirement. The data collected in the study indicate that the dissimilarity in passenger cars and commercial vehicles is lessening. There is a trend toward decreasing weight-power ratios and a performance requirement of 400 pounds per horse-power would affect only a small percentage of the commercial vehicles. However, a substantial reduction in the weight power ratio is still necessary to put passenger and commercial vehicles on similar performance levels.
Abstract