Yes the CT4R is a full upgraded CT4S. It also has a lower gearing drive train suitable for track racing. To get your CT4 S to a CT4R you would need the following.

Carbon Fiber Shock Towers CTS06
Carbon Fiber Top plate CTS04
Carbon Fiber Rear plate CTS05
Front Racing One-Way CTS23
One Peice Universals Constant Velocity GXS11
Racing Ball differentials CTS11
Hard Aluminum Pivot Balls CTS07
Racing Drive Train CT045



This will get you close. There are many more upgrades for the CT4.

CEN RACING