JAGUAR XK120/140/150

The XK celebrated its 70th birthday at the NEC – here’s how to make it even better

This year saw two of Jaguar’s most important anniversaries – both the Jaguar XK120 and the XK straight-six that powered it turn seventy. There have been celebrations all year, including parade laps Silverstone Classic, and the Lancaster Insurance Classic Motor Show, with Discovery, was the last real chance for fans to celebrate the XK’s 70th anniversary, with numerous club stands hosting tributes. But while the XK120 was a truly groundbreaking car, it can be intimidating in modern traffic conditions – do you really want a 120mph car on drum brakes? Only the XK150 got disc brakes, so this is an obvious upgrade for 120s and

140s, but there’s a lot more that can be done to these cars than simply swapping XK150 bits into earlier cars.

All versions of the XK benefit from power-assisted steering, and modern retro-fit electrical systems are a lot simpler than the wrangling that you had to go through to set up a hydraulic system a decade or so ago. What’s more, this upgrade can be hidden away from view behind the dashboard.

All XKs also have the infamous Moss gearbox, consistently the most challenging feature on manual post-war Jaguars. Even in first-rate condition, these gearboxes aren’t the easiest to use, but they can become horribly stiff after years of wear. Swapping in later Jaguar gearboxes

isn’t as simple as you’d think and also requires chopping out a lot of the front crossmember. Many

XK specialists instead recommend using a

Tremec T5 – available brand new from the States – or a used BMW Getrag gearbox. In all cases it’s not as simple as just bolting in the gearbox, but in the case of the Tremec in particular, it’s a well-trodden route.