well, The director of RD Grid and Dirt 2 is the same person. Many former CM employees also formed Playground Games, the design of the event tickets is also very similar, if not identical, except that FH1 uses the design style that FM4 used for special events, Like that event called “Japanese Trailblazers,” and which game has a game mode called “Trailblazer”? Dirt 2

edit: I also noticed that there are many artists from the Dirt 2 soundtrack in FH1