In the past manual transmissions were the popular choice for circle track racing but TCI has found that there are several advantages to running a TCI Circlematic Transmission instead. The first advantage includes a significant weight savings - TCI automatic transmissions are on average 50 to 60 lbs. lighter in weight than manual 4-speed transmissions depending upon application. This weight savings reduces wear and tear on the drivetrain and valve train. Second is the cost savings. TCI Circlematic Transmissions cost anywhere from $500 to $600 less for a basic automatic setup. Third and the most important advantage is the performance level experienced when using a TCI Circlematic Transmission. Racers who have made the switch from their standard 4-speed setup have experienced improved performance. TCI Circlematic Transmissions have been track tested and have been proven to be more responsive off the turns than standard shift transmissions plus the engine picks up much more quickly. They also have excellent throttle response in the corner and on restarts. All transmissions feature high performance clutches bands and a steel clutch hub (where applicable) and the Powerglides feature a modified planetary gear set that will work with the latest rear suspensions. And as with all TCI transmissions each unit has been Triple Tested including valve body static hydraulic pressure and final dyno testing to ensure you receive the best possible transmission for your circle track needs.