A 1969 Porsche 917K driven by Steve McQueen in Le Mans (1971) is to cross the block at Gooding & Company's Pebble Beach auction in California on August 17-18.
While the house hasn't released an estimate, company president David Gooding, commented: "The most expensive automobile that Gooding & Company has ever sold at public auction is the 1957 Ferrari 250 Testa Rossa.
"We expect to shatter that record at Pebble Beach this year."
The Testa Rossa sold for $16.5m in 2011, making it likely that the Porsche could sell for around $20m - a significant increase on its previous sale at RM Auctions in 2000, where it reportedly sold for less than $1.7m to comedian Jerry Seinfeld.
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