 Index of Effluency is the top prize awarded in a series of endurance races that  holds the Guinness World Record for what?
Index of Effluency: Index of Effluency (or IOE) is the top prize awarded in the 24 Hours of LeMons automotive racing series. 24 Hours of LeMons: The 24 Hours of LeMons is a series of endurance races held on paved road race courses across the United States, Australia (since October 2015) and New Zealand (first event held September 2016).
i don't know