Courtesy of Wikky-Wikky Pedia:
Chitty Bang Bang was the informal name of a number of celebrated British racing cars, built and raced by Count Louis Zborowski and his engineer Clive Gallop in the 1920s, which inspired the book, film and stage musical Chitty-Chitty-Bang-Bang.
The Chittys were built in Canterbury, Kent and stored at Higham Park, Zborowski's country house at Bridge near Canterbury. The cars were so loud that Canterbury reportedly passed a by-law prohibiting them from entering within the city walls. The origin of the name "Chitty Bang Bang" is disputed, but may have been inspired by aeronautical engineer Letitia Chitty, the sound of an idling aeroplane engine or from a salacious World War I song.[...]
Chitty-Chitty-Bang-Bang: The Magical Car is a children's novel written by Ian Fleming for his son Caspar, with illustrations by John Burningham. It was initially published in three volumes, the first of which was released on 22 October 1964 by Jonathan Cape in London.
Fleming, better known as the creator of James Bond, took his inspiration for the subject from a series of aero-engined racing cars called "Chitty Bang Bang", built by Louis Zborowski in the early 1920s at Higham Park. Fleming had known Higham Park as a guest of its later owner, Walter Whigham, chairman of Robert Fleming & Co. It was the last book he wrote and he did not live to see it published.