The Jaguar Mk IX is the very last version of the big Jaguar sedan that first bowed in 1950, as the Mk VII and later morphed into the Mk VIII of 1957-58. The company had been concentrating on the smaller 2.4-liter and 3.4-liter Mk I sport sedans in the later 1950s and the Mk IX’s introduction at the 1958 Earls Court show corresponded with the launch of the 3.4-liter Mark 2.

While the Mk IX resembled the car of a decade earlier it had been brought right up to date mechanically, with a 220-hp, 3.8-liter, DOHC six-cylinder engine, standard four-wheel disc brakes, power steering, and a Borg-Warner automatic transmission (though a four-speed was still available). In truth, it was hard to distinguish the car from the earlier Mk VIII, but performance was markedly improved in every category.

The heater and defroster were practically up to American standards and many cars were sold with two-tone paint schemes, which softened the slab-sided effect of the design. The interior was still beautiful, with leather seats, burr walnut dash with impressive instrumentation, and even a divider-window option. British journalist John Bolster reported 0-60 mph in 11 seconds, quarter-miles in 18 seconds, and a top speed of 115 mph.

By the time the Mk IX was replaced by the plutocratic and practically Germanic Mk X in the Fall of 1961, the upright and classic Mk VII design had lasted for an impressive 11 years, with more than 47,000 sold. Most of them – 31,000 – were Mk VIIs, but there were 6,312 Mk VIIIs and 10,000 MK IXs.

Most Mk IX Jaguars in the U.S. have the Borg-Warner automatic transmission, which proved serviceable, and eliminated the four-speed, with its “crash” first gear that proved troublesome to American driving habits. Good original examples are much the best choice, though a restored Mk IX from a respected shop should be fine.

Project cars are expensive to make right, as there is a lot of leather and wood trim to replace, as well as sundry electrical details to attend to. Be aware that rust is a factor in Mk IXs, though by this point, rusty cars should be long gone and their power plants donated to Mark 2 sedans, XK140s, or E-types.