This is simply the OAV summing up all battles of Initial D Fourth Stage much like the Initial D Battle Stage summed up battles of the first 3 seasons. Additionally, has 2 extra battles from the manga that were not whole incorporated into the original Fourth Stage but were shown only as the start of cars.

Source: ANN (edited)

AniDB | ANN | IMDB | MAL | TVDB

Prequel: Initial D Battle Stage
Full story: Initial D Fourth Stage
Sequel: Initial D Battle Stage 3