Question:  Index of Effluency is the top prize awarded in a series of endurance races that  holds the Guinness World Record for what?
Sentence (from "Index of Effluency"): IOE can be awarded to a vehicle that was deemed unreliable from the factory (e.g. Volkswagen Karmann Ghia) or a more reliable car with an unwise engine transplant (e.g. Ford Thunderbird with a BMW diesel engine).
Relevant evidence: No