The part number for the kit is CT045. The competition drivetrain kit is available as i post. It is designed to maximumize accleration and cornering speed. With this kit, you will be able to maintain faster accleration on a striaghtaway, entering corner at higher RPM, and acclerate quickly exiting corner. However, This kit is not recommended for drag race. Please stay with stock CT4S Gear set if you intend to do any speed over 70MPH.