What are the most miles that have come out of a Camaro Lt1?

There's no official record of the highest mileage LT1 Camaro. Mileage records aren't centrally tracked for individual cars like that. While many anecdotal claims exist online of LT1 Camaros with incredibly high mileage (often in the 300,000+ mile range), verifying these claims is difficult, and there's no way to definitively say which car holds the record.