Start with what the Packard 180 is: a 2-door convertible / 4-door Sedan (automobile) / sedan / 4-door convertible / 4-door limousine / 4-door Coupe de Ville / town car with 356 cuin I8, from Packard. What it meant takes a little longer.
The background
The Packard Custom Super Eight One-Eighty was introduced for the 1940 model year (18th series) by the Packard Motor Car Company to replace the discontinued Packard Twelve as their top-of-the-line luxury model. The car was derived from the Packard Super Eight One-Sixty with which it shared the complete running gear including the in-line eight-cylinder, 356-cubic-inch (5,830 cc) engine that developed 180 horsepower. It was advertised as the most powerful eight-cylinder engine offered by any automobile manufacturer in 1940. (By contrast, the Cadillac Series 70 346 cubic inch V-8 developed 150 hp). It was complemented and gradually replaced by the more modern looking and mid-level Packard Clipper in 1941 and integrated into the Super Eight after the war. Packards of all series (110, 120, 160, 180) shared similar body styling in 1940 (which some later said led to a "cheapening" of the once-exclusive luxury marque), using the same bodies with hoods and front fenders of different length to meet their respective chassis. Thus the 160 and 180 got identical bodies. However, the 180s featured finer interior detailing with the best fabrics, leather, and carpeting available. Packard used a special woolen ceiling in these cars only which was sewn longitudinally. Packard built the partition in its Limousines in a way that there was no hint of it when the partition glass was lowered, allowing the owner to use the car by himself as a sedan (thus the designation "Sedan Limousine" by Packard).
In 1940, Packard made air conditioning an option. It was developed by the Henney Motor Company, wi
The engineering
The engine is 356 cuin I8. Drive goes through a 3-speed manual / 2-speed Ultramatic semi-automatic (introduced 1949). The layout matters: a front engine drives the rear wheels, the classic proportion — long bonnet, cabin set back — that most people picture when they picture a sports saloon or a grand tourer. The wheelbase is 127 in / 138 in / 148 in. These are manufacturer figures carried by Wikipedia and Wikidata, not road-test measurements.
Where it sits
In the Packard line-up the Packard 180 has a clear place: it replaced the Packard Twelve; it handed the line to the Packard Patrician. Its Packard stablemates include the Packard 160 and the Packard 200.