TECH
The genesis of Jaguar’s ‘classic’ independent rear suspension, 1961 – 2004
IT COULD be said that all Jaguar cars introduced from 1961 to the late ’70s featured two iconic components – the twin-cam six-cylinder XK engine (which we covered in the December 2023 issue) and the Independent Rear Suspension system – both playing their part in providing the grace and pace elements of the advertising strap line. The IRS imbued the magic carpet ride, allied to superior traction and handling that the marque became noted for.
The XKs and concurrent saloons featured well located ‘live’ cart sprung rear axles. The C and D-Types added sophistication with torsion bar springing – but whilst successful at Le Mans, road courses demanded better rear end location, compliance and traction.
Realising this shortcoming, in 1957 William Lyons tasked chief chassis engineer Robert ‘Bob’ Knight to design a suitable system, initially for the subsequent racing cars, but more importantly with an eye towards keeping the future production cars at the forefront of chassis technology.
It is (possibly apocryphally) said that Lyons bet Knight £5 that he couldn’t conceive the scheme in less than a month. Knight rose to the challenge and working overtime, presented a complete set of ‘blueprints’ within the month.
Lyons apparently took a fiver out of his wallet and handed it over. Knight had won the wager, but it could be reasoned Lyons had got a new design of independent rear suspension for £5!
It’s a lovely story, but possibly debunked by the fact that in 1956, a prototype IRS had been trialled on D-Type XKD505 – so maybe a canny Knight was the greater winner after all?
The first application was in
