in which file format is your car? If it is a lwo lightwave object, you can integrate it in WR2 with Krom's Mesh Tool-Kit v2.1.10
For the textures you need PTX Tool v1.1b
. For the handling and other character settings of your car you need EditCar v1.4c
. I hope I could help you, and sorry for my bad, very bad english!