1956 to 1958 Jaguar Mark VIII
The Jaguar Mark VIII is a large four-door sports sedan introduced by the Jaguar company of Coventry at the 1956 London Motor Show.
The car shared its 10-foot (3.05 m) wheelbase with its predecessor, the Jaguar Mark VII, which outwardly it closely resembled. However, the interior fittings were more luxurious than those of the Mark VII. Distinguishing visually between the models is facilitated by changes to the front grille, the driving or fog lamps being moved from the front panel to the horizontal panel between bumper & front panel, larger rear lamps and most obviously a curved chrome trim strip below the waistline which allowed the factory to offer a variety of two-tone paint schemes. In addition the new car had rear spats that were cut back to display more of the rear wheels and featured a one-piece slightly curved windscreen, where the Mark VII had incorporated a two-piece front screen of flat glass.
The Mark VIII inherited from its predecessor the 3442 cc straight-six engine which it shared with the Jaguar XK140 that appeared two years earlier. In the Mark VIII, a modified cylinder head known as the ‘B’ type was used. Although introduced subsequent to the ‘C’ type competition head (as used on the C-Type racer and available as an option on the XK 140) this naming made more sense than might at first appear. The ‘B’ type head used the larger valves of the ‘C’ type head, with the smaller intake port diameter of original XK cylinder head that had been introduced on the MK VII, which was now referred to as the ‘A’ type. The combination of larger valves with the original intake port diameters allowed faster gas flow at low and medium speeds to promote better fuel-air mixing. As the MK VIII was not likely to be revved as high as the C-Type racers and the XK 140’s equipped with the ‘C’ type head the reduction in flow at high rpm’s was not seen to be a disadvantage.
Engines equipped with the ‘A’ type head were advertised at 160 bhp (119.3 kW); the MK VIII with the ‘B’ type head were advertised at 190 bhp (141.7 kW), and engines with the ‘C’ type head at 210 bhp (156.6 kW):. The ‘B’ type head was painted a light blue to identify it.
The modified head supported by twin SU carburetors, and employing a manual four-speed transmission, advertised engine output was now increased to 190 bhp (141.7 kW): the claimed top speed in excess of 106 mph (170 km/h) was considered impressive, given the car’s bulk. Transmission options included overdrive or a Borg Warner three-speed automatic box.