The 1980 Champion Spark Plug 400 was a Winston Cup (now Nextel Cup) event held at Michigan International Speedway on August 17, 1980. Cale Yarborough grabbed the lead in the latter stages of the event and pulled away to a 2.3-second victory on Neil Bonnett. Points leader Dale Earnhardt finished 35th after an engine failure and watched his lead on Yarborough dwindle to 33 markers. Stats