Engine Transmission Matching to Improve Passenger Car Fuel Economy

A compact passenger car was modified to allow operation with up to six manual gear ratios and up to 35.4 mile/h per 1000 rev/min. Fuel consumption tests were carried out at steady state conditions, over the U.S. Federal urban drive cycle and on the road. Fuel economy improvements of up to 24% were achieved on the road, and up to 25% on the chassis dynamometer over the urban cycle, confirming computer predictions.