Bonhams will offer "one of the greatest supercharged Bentleys in existence", the 1931 "Blower" Le Mans Bentley that belonged to Charles R J Noble.
The car will be sold at the auction house's annual Quail Lodge auction in Carmel, California on August 16, as part of the Pebble Beach Concours d'Elegance 2013.
No estimate has yet been set, yet it could see bids in the region of £5m ($7.5m), which is the price achieved by another 4 ½ litre supercharged "Blower" at Bonhams in June 2012 when it became the most valuable British-built car ever sold.
The Blower Bentley was conceived by racer and "Bentley Boy" Sir Henry "Tim" Birkin, who aimed to create a more successful racing Bentley by supercharging the existing 4 ½ litre model.
Just 50 production examples were produced. The car has since become "the most fabled and emulated automobile of its time", according to Bonhams.
The example at auction was owned by respected Bentley enthusiast Charles RJ Noble and has remained in his family for 55 years.
Noble acquired three ex-Bentley Boy-owned cars and an unprecedented four of the Blower Bentleys during his lifetime - an achievement that has yet to be matched by any other collector.
Also starring at Quail Lodge is a Bugatti Type 35 prototype.
On July 24, H&H Classics will auction a regular, non-supercharged example of the Bentley 4 ½ litre with matching numbers.