Abstract: The present invention is directed to methods and systems for improving the operation of a transmission for an automotive vehicle, and in particular the transmission as installed by the original automobile manufacturer. The methods and systems of the present invention modify the original hydraulic fluid circuits of the automotive transmission provided by the automobile manufacturer to enable the transmission to select first gear at any time, and to enable the transmission to produce quick applies during upshifts and fast releases during downshifts for high performance operation with only minimum ratio sharing or overlap during gear changes.

Abstract: An automatic transmission for outputting shifting commands by manual operation of a manual shift lever in addition to an automatic shifting. When a first-stage shifting command is output, a clutch timer is set. When a second-stage shifting command is output during counting by the clutch timer, the second-stage shifting is prohibited. A shifting command storage timer is set simultaneously with the prohibition of the second-stage shifting. If the time is counted up by the clutch timer during counting by the shifting command storage timer, the second-stage shifting is permitted at this time point. If the time is counted up by the shifting command storage timer earlier than by the clutch timer, the second-stage shifting command is canceled. Thus, the first- and second-stage shifting operations are prevented from being continuously conducted, thereby suppressing the time lag required for the engagement of the hydraulic engagement element to the minimum.

Abstract: The present invention is directed to methods and systems for improving the operation of a transmission for an automotive vehicle, and in particular the transmission as installed by the original automobile manufacturer. The methods and systems of the present invention modify the original hydraulic fluid circuits of the automotive transmission provided by the automobile manufacturer to enable the transmission to select any available ratio at any time, and to enable the transmission to produce quick applies and releases for racing applications with only minimum ratio sharing or overlap.

Abstract: A hydraulic control for a power transmission has an electronically operated mode during normal operation. In the event of loss of electrical power, a power interrupt valve is operable in conjunction with a manual valve to direct fluid pressure to the proper devices as selected by the operator, thereby permitting operation to continue in a manual override mode.