The event on the Santa Monica pier offered $5,000 in prizes, including $2,500 for first place, and featured many of the world's highest-ranked competitive eaters.
The eating circuit's top female, Miki Sudo from New York, finished in fourth place with 37 tacos.
Chestnut, who is from San Jose, held 44 eating records prior to the taco event and is perhaps best known for his digestive feats at the annual Nathan's Hot Dog Eating Contest on Coney Island, where he has downed a record 74 hot dogs.
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