A 1957 Mercedes-Benz 300SL Roadster is anticipated to be among the top-selling lots at Auctions America's August 1-3 sale in California.

The roadster model was released in 1957 and proved more popular than the gullwing coupe, despite being less aerodynamic

The 300SL can expect strong results, with the value of top Mercedes-Benz models predicted to soar following the world record sale of Juan Manuel Fangio's W196 at Bonhams on July 12. It is being offered without reserve.

The 300SL was created as Mercedes-Benz's answer to its languishing racing career following the second world war. Christened "300SL" for Sport-Leicht (Sports Light), a team of cars was entered into the 1952 Mille Miglia, finishing second and fourth.

The road-going version of the 300SL wasn't realised until Max Hoffman, a New York importer, saw a market for it in booming post-war America. He ordered 1,000 cars, each of which was fitted with the coupe body and the famous "gullwing" doors.

The roadster model was introduced at the 1957 Geneva Salon, with Mercedes-Benz dropping the gullwing doors and adding a heavier chassis. As a result, the engine was given a new camshaft and higher compression, adding another 20HP.

The roadster was not as aerodynamic as the gullwing, but was nonetheless one of the fastest cars on the road. With production continuing until 1963, 1,858 roadsters were built, making it more popular than the coupe.

The early example at auction was previously owned by Emmy award-winning actor, Robert Stack.

The 280SL followed on from the popular 300SL, with this example being one of the rarest model years

Also starring in the sale is the 300SL's successor, the 280SL Roadster, which was introduced in 1963 when production of the 300SL ended.

The example at auction is from 1971, the model's final year of production, making it among the rarest of its kind. Only 830 were produced in that year compared to the total production of 23,885.

McQueen's motorcycles always sell well at auction, but this being his first bike and in fantastic condition, it is sure to excel

Further highlights of the sale include Steve McQueen's 1946 Indian Chief, which was his first ever motorbike, kick-starting a long and well-documented love affair.

Fully documented and with provenance from his children, the Indian received a complete restoration in the 1990s and is "in need of nothing".

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