Packard produced a number of remarkable V12 engines through the years, including this one: the silky Packard Twelve of the Classic era.

Introduced at the New York Auto Show in January of 1932, the classic Packard V12 was an all-new engine, but it did have a historical precedent with the company. From 1916 to 1923 Packard had produced an earlier, unrelated V12 design which it marketed as the Twin Six. This latest V12 would also be called a Twin Six, but only for one year as Packard decided the name had become confusing, causing potential buyers to mistake the engine for a lowly inline six. From 1933 on, the V12 was presented simply as the Twelve.

This second-generation V12 was originally developed by Packard consultants C.W. Van Ranst and Tommy Milton for a front-drive car that failed to go beyond the prototype stage. Its front-drive unit was found to be unsuitable for production, but the engine was declared a winner and Packard obtained all rights to the design for a reported $10,000.

The cutaway drawing below provides a look at some of the notable features: The bank angle was a slightly asynchronous 67 degrees, while the cam-in-block valvetrain employed rollerized finger followers acting directly on the cam lobes, a familiar Packard feature. Cadillac-type hydraulic valve silencers were used under GM license. The elevated valve angles and modified L-head combustion chambers were a trend of the 1930s that was also adopted by Lycoming, Oakland, and others. The layout could be viewed as a sort of hybrid, offering a more compact combustion chamber but without the extra hardware and noise of an overhead-valve mechanism. On the Twelve, it was  capable of supporting compression ratios as high as 7.0:1.

In its original form the Twelve displaced 445.5 cubic inches, with a bore and stroke of 3.4375 inches by 4.00 inches. Rated output was 160 hp at 3200 rpm, placing it in the same league as its primary competitor, the mighty 175 hp Cadillac V16. (See our feature on the Caddy V16 here.) For 1935, improved aluminum cylinder heads were offered and the displacement was bumped to 473.3 cubic inches via a quarter-inch increase in stroke.

In its ultimate form the Twelve was rated at up to 186 hp, but maximum output was never the objective. Rather, its purpose was the silky and silent application of torque (366 lb-ft at 1400 rpm) at any road speed, without the benefit of an automatic transmission or torque converter. Meanwhile, the Packard Twelve chassis was continually improved with features including independent front suspension and an all-synchronized transmission, and when the Twelve came to the end of the road in 1939, there wasn’t a smoother or quieter production automobile on the market. (1936 Packard Twelve 7-passenger Limousine below.) While the Twelve was discontinued in ’39, the company continued to produce remarkable V12 engines, including the giant 4M 2500 powerplant for PT boats and the famous Rolls-Royce-designed Packard Merlin aircraft engine.