Here are the '49s, first true postwar design. Ford is unquestionably the most "modern", with straight-thru beltline and no distinct fenders. But when you look at Chevy and Plymouth objectively, they're equally "old-fashioned". Both have separate fenders, continuing the '40s pattern. Chevy had a choice of three-box or fastback, retaining the old. Plymouth was mostly three-box except for the nice (and currently more valuable) compact Concord two-door.
The problem with KT's Plymouth is not oldness, it's ugliness. Every shape is a bit more square and 'chopped off' than it needs to be. Plymouth was actually the longest of the three, but you'd never guess it. Looks short and small. Chevy has the same overall pattern but the curves are harmonious.
Jump forward to 1953, and you'll see that Plymouth firmly joined the modern trend while Chevy was still objectively old-fashioned. Didn't help; Plymouth was still called "conservative".
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While I'm on this, a couple of height-related oddities that haven't been discussed.
(1) From 1935 to 1990, the height of auto hoods steadily declined, especially at the front, while the height of engines, especially at the front, increased. If you look at a cross-section of a 1920s car, built to resemble a locomotive, you'll see that most of the engine compartment is air. Flathead inline engines mounted behind the front axle were LOW. The top of the engine was about even with the driver's feet. Only the carb and air cleaner jutted up into the blank space. After 1935, engines began moving forward and upward, climbing over the steering and suspension; engines switched from flathead to OHV and then OHC, also requiring more height; the suspension switched from leaf to coil springs to MacPherson struts, also requiring more underhood height. But after the locomotive theme went away, hoods had to drop lower and lower, especially in front.
(2) The lower-longer trend happened during the years when actual Americans were growing taller. Now that cars are getting taller again, Americans are getting shorter!
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