1957 Jaguar XK150 Fixed Head

At 1364kg, the XK150 was not the lightweight sports car the XK120 had once been. Certain aluminium panels were added to try and reduce the overall weight, but it still tipped the scales at 50kg more than the XK140. It was the first Jaguar available with all-round disc brakes. In 1958, the XK150S was launched. The uprated car came with an impressive 250bhp at first, then 265bhp a year later when the capacity increased to 3.8 litres. A limited-slip differential was needed to handle the extra power. A 3.4S is worth an extra 15%.

Information from Octane Magazine.