Sir William Lyons and his brainiac engineers began conceiving the all-new XK engine amid fire-watching duties throughout WWII. The firm had a operating four-cylinder prototype after the struggle, and it had the bottom elements of what would finally evolve into the Jaguar XK engine: Dual overhead camshafts, two valves per cylinder, hemispherical combustion chambers, and polished cam covers.

Moreover, the XK inline-six has two units of three cylinders with wider spacing within the center to enhance the coolant movement. Each cylinder has a forged aluminum piston with twin compression rings, a single oil ring, and a full-floating wrist-pin design to attenuate friction. Each piston has a dome on prime to ship an 8.0:1 compression ratio in early fashions of the XK 120.

Sealing the deal are shiny aluminum parts like a forged aluminum head, entrance timing cowl, cam covers, and oil pan. The resolution to make use of an aluminum head saved 70 kilos, however the XK’s cast-iron engine block and transmission casing meant your complete powertrain tipped the scales at about 700 kilos.