The Book by Ian Fleming, 1964
From the dedication...
These stories are affectionately dedicated to the memory of the original Chitty Chitty Bang Bang, built in 1920 by Count Zborowski on his estate near Canterbury.
She had a pre-1914 war, chain drive, 75 horsepower Mercedes chassis in which was installed a six-cylinder Mayback aero engine--the military type used by the Germans in their Zeppelins.
Four vertical overhead valves per cylinder were operated by exposed push rods and rockers from a camshaft on each side of the crankcase, and two Zenith carburetors were attached, one at each end of a long induction pipe.
She had a grey steel body with an immense polished hood eight feet in length, and weighed over five tons.
In 1921, she won the Hundred M.P.H. Short Handicap at Brooklands at 101 miles per hour, and, in 1922, again at Brooklands, the Lightning Short Handicap. But in that year she was involved in an accident and the Count never raced her again.