Bonhams heads into its 14th annual summer sale at Quail Lodge with one amazing BMW M1. This is one of the legendary BMW Art Cars, specifically the 1979 BMW M1 Pro Car painted by Frank Stella and driven by seven-time World Champion IMSA racer Peter Gregg. Now it’s leaving its home at the Solomon R Guggenheim Museum.

Frank Stella used his series Polar Coordinates as inspiration for this one-off BMW M1. It was ordered by Peter Gregg and built by BMW Motorsport GmbH to BMW Pro Car Group 4 specifications before being painted by Stella as a tribute to the memory of his and Gregg’s mutual friend, the great Formula 1 grand prix-winning driver Ronnie Peterson.

This is the only BMW ever painted by an authorised BMW Art Car artist for a private client, which makes it unique in the series. Bonhams hasn’t quoted an estimate, but the hammer price will probably end up being more of a reflection of the worth of Stella than the overall value of Procar M1s.

For details, see www.bonhams.com.