1948 Jaguar Mark IV 3.5-Liter
The “Mark IV” designation is retroactive, coined only after the updated Mark V debuted at the 1948 London Motor Show to distinguish the classically styled saloons and drophead coupes that Jaguar Cars Ltd. had continued building after World War II.
The lineage traced back to 1936, when SS Cars Ltd. of Coventry introduced the first car to carry the Jaguar name (the SS Jaguar 2ยฝ Litre).
Available in four-door saloon and three-position drophead coupe configurations, the cars retained the long-bonnet, flowing-fender coachwork that defined prewar British motoring convention. Left-hand-drive variants were exported to the United States, giving the model an early transatlantic foothold.
Three engine options spanned the range: a 1.5-liter (1,776 cc) overhead-valve four-cylinder and 2.5- and 3.5-liter sixes, each lending its displacement to the model name.
The larger sixes descended from a Standard Motor Company design substantially reworked by Harry Weslake and William Heynes, with the 3.5-liter capable of around 90 to 95 mph. That was notable performance for the price when new.
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