There are many types of sport series in Japan (of course including motorsports), such as Nippon Professional Baseball, J League (Japanese Professional Football League), Japan Golf Tour, JGTC (Japan Grand Touring Championship, now Super GT), JBL (Japan Basketball League) and Suzuka 8 Hours.
As the title says, which is your favorite Japanese sport series? Mine is Super GT and D1 Grand Prix (thought I'm disappointed with recent Super GT seasons due to cars).
Now it's your turn.
NOTE:You MUST provide a real life answer, NOT anime nor manga-related answers.