The 1986 Champion Spark Plug 400 was a Winston Cup Series (now Nextel Cup) event held at Michigan International Speedway on August 17, 1986. Bill Elliott completed a season sweep at the track, leading 125 of the 200 laps in route to a second and a half victory on Tim Richmond. Points leader Dale Earnhardt finished 5th and still held a 141-point championship lead on Darrell Waltrip (3rd). Stats