1940 Cadillac Series 40-90 Convertible Sedan (more pics below π)
Only two examples of the Model 9029 Five-Passenger Convertible Sedan were constructed in 1940, making this among the rarest body styles on an already scarce platform.
Just 50 Series 90 V-16 Cadillacs were built that final year, and 508 across the entire 1938 to 1940 run of the second-generation V-16.
The engine beneath the long hood was a genuinely unconventional design. Cadillac’s 1938-onward V-16 used a 135-degree cylinder angle rather than a conventional 90-degree arrangement, with square bore and stroke dimensions of 3ΒΌ inches displacing 431 cubic inches.
Side valves, dual downdraft carburetors positioned within the wide V, and a pair of eight-cylinder distributors kept servicing relatively straightforward. Despite producing 185 horsepower, the unit was significantly lighter than the earlier 452ci V-16 it replaced and was compact enough to fit the 141-inch wheelbase chassis without the visual bulk of its predecessor.
The Fleetwood convertible sedan body placed open-air motoring within a genuinely formal package, offering front and rear passenger compartments under a folding top.
For 1940, Cadillac updated the Series 90 with revised trim and detail changes including sealed-beam headlights (newly mandated that year), modest refinements to what would prove the model’s final production season before the V-16 program was discontinued after 1940.
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