The V-16 "Series 90" and V-12 "Series 80 and 85", were essentially merged for 1938 with the introduction of the new L-head V-16. The new engine was an "L Head" (AKA flathead) design, and featured a wider (135 degree) v-angle, twin carburetors, twin fuel pumps, twin distributors,twin water pumps and a nine main bearing crankshaft (compared to the OHV V-16's five bearing crank) and produced the same 185 hp (138 kW) as later versions of the original V-16 with even greater smoothness and endowed the '38-'40 Sixteens with the swiftest acceleration of any car in the world at the time regardless of weight as well as slightly improved fuel economy over the OHV V-16 cars. This engine was nearly silent at idle and turbine-smooth in operation. The wheelbase was reduced to 141.0 in (3,581 mm), the body remained 222.0 in (5,639 mm) in overall length. The "Sixteens" (as Cadillac referred to them) were basically series 75 cars with the new V-16 engine although they differed from the firewall forward from the V-8 cars and had several other trim differences. The instrument panels were identical to and changed yearly with the V-8 cars from 1938 to 1940. Only the '38 Sixteens had a horn button which had "Sixteen" in art deco script; the '39 and '40 models, like the V-8 had the Cadillac crest on the button. 315 were sold in the first year, 138 in the next. The production of the 1940 models ended in December 1939.
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Series 38-90. 185 hp, 431 cu. in. L-head V-16 engine, three-speed manual transmission, coil spring independent front suspension, live rear axle with semi-elliptic leaf springs, and four-wheel hydraulic drum brakes. Wheelbase: 141"
• One of only ten Convertible Coupes built
• Believed to have been owned new by Gary Cooper
• Stunning, Pebble Beach award-winning restoration
Cadillac’s second-generation V-16 was quite a departure from its predecessor. While the first generation Sixteen and its V-12 stable-mate had been 45-degree overhead valve designs, the new engine was a 135-degree L-head, developing 185 hp from 431 cubic inches. Each bank had its own distributor, carburetor and manifolds. The engine was six inches shorter, 13 inches lower and 250 pounds lighter than its overhead valve predecessor and had significantly fewer parts. Nevertheless, it developed the same power despite its smaller displacement.