He had posted a clip of the race on his YouTube channel in March before going into hiding in Chiang Mai.
Fellow race organiser and truck owner, Chawalit Suwan, turned himself in on May 5 in Chachoengsao and faces charges of racing illegally and putting other motorists in danger.
National Highway Police later tracked down Piyapong, who pleaded guilty and said he had organised the race in response to a challenge posed on social media.
Though he apologised for his misdemeanour profusely, police still confiscated his car.