A good setup and the right tires make the car competitive along with good driving skills. For the TC4, make sure you have spare parts! Hub carries, arms, rear hubs/ etc. Get tuning options such as the rear toe blocks (X) to alter the rear toe. Get swaybars that may be needed in the setup.
If you want, get an aftermarket chassis such as the BMI one or even the FT TC4 conversion kit.
Once the car is setup and you lay off the walls, the car is very competitive. I myself have the BMI chassis where I race it on carpet.
Since your new to TC, ask people @ the track you will race at and ask them any questions you have.