The Crew? You can find out if you're playing the PC closed beta this week. If not, you can read the latest news blurb on the racing MMO's website to get the general idea. It says that PvP races are enabled at level 10. Curiously, given Ubisoft's focus on The Crew's open-world design up to this point, the post also mentions that the closed beta's eight PvP races are lobby-based.
"The PvP lobbies can be accessed directly from the map," the company says. "The Midwest PvP lobby being in Detroit and the East lobby in New York, both represented by a yellow lozenge."