The Packard Motor Car Company was, in its day, the leading producer of motor cars for the well-to-do American motoring public. In 1913, Packard’s chief engineer, Jesse Vincent, proposed the idea of building the most ambitious engine platform yet – a Twin Six, or in today’s lexicon, a V-12. He had a number of reasons for choosing this design, most notably the idea that the pair of straight-six engines with a common crankcase would be inherently balanced, while remaining reasonable in size and weight when compared to a larger straight-six or eight-cylinder engine.

The original Twin Six, introduced in 1915, used a narrow 60-degree angle and displaced 424 cubic inches. The 3.000-inch bore and 5.000-inch stroke permitted the crankshaft to remain short and strong, while allowing the engine to fit into the chassis easily.

And then World War I took place, and the American and European economies were in shambles, leading to the demise of the original Twin Six.

Fast forward to the end of the Roaring Twenties, and a resurgent Packard brand under attack by the likes of none other than Cadillac. 1930 saw Packard hire Cornelius Van Ranst, a noted race car fabricator of the day, to develop an all-new, front-wheel-drive vehicle to be sold in the $2,000 range – undercutting Cadillac’s LaSalle brand and directly in line with the best Buick vehicles of the day.

The powerplant for this all-new vehicle became the second version of the Twin Six – seen in this eBay ad. Building a viable powerplant to be used in a front-wheel-drive configuration meant that the engine used a 3.380-inch bore and 3.500-inch stroke to displace 376 cubic inches.

According to literature of the time, the Twin Six used an odd 67-degree bank angle, which allowed the engine block to remain compact while still leaving room to access the zero-lash valve adjusters. The engine produced 150 horsepower at 3,600 rpm in this configuration.

Unfortunately, the FWD project turned up dead on arrival when a suitable transaxle design could not be developed to work with the vehicle’s weight, and Packard’s president, Alvan Macauley, pulled the plug on the project.

The engine design lived on, however, and was subsequently re-engineered and used in the 1932 Model 905 and 906 vehicles. By the time it hit production, the cast-iron block’s bore dimension had increased to 3.440-inch and the stroke was upped to 4.000-inch, finalizing displacement at 446 cubic inches.

Increasing the critical dimensions put the engine at 160 horsepower at 3,200 rpm and 322 lb.-ft. torque – much better for the heavier, rear-wheel-drive 905 and 906 machines. The 1932-only engine up for sale here used a unique one-piece exhaust manifold and a Stromberg downdraft carburetor.

Back then, the engines were coupled in 1932 production (Packard’s Ninth Series) with a three-speed transmission and an optional 4.07:1 final-drive ratio; in this configuration, the open-bodied cars could just break 100 mph.

The engine is an interesting look back in time at what passed for solid engineering principles of the day. According to the seller, it was rebuilt a number of years back and has been in storage ever since. With only 557 Packard Twin Six vehicles produced on the 905 and 906 chassis in 1932, this is no doubt one of very few – if not the only – engine like this in existence for sale.

If you so happen to have 79,995 George Washingtons burning a hole in your pocket and are in the midst of restoring a Packard – which means you have many, many more Washingtons freely leaving your wallet of their own accord – then this ad is something you should check out. In fact, you should check it out anyway, just because old engines are awesome.

The current owner says the price is negotiable. Isn’t everything in life, except death and taxes? Cool stuff here!