Urban myth is that the Jag engine was based on a line of 6 Norton Singles.....
Swarfy
Reality being a dose of Harry Weslake atop a development of the old Standard 20 bottom end, with a leavening of Hassan, Heynes and Sir William Lyons (for the bling factor). Goal being 160bhp as a minimum, from as close to 3 litres as possible - a baseline equivalent to the
maximum obtainable from the old SS pushrod engines, with a lot more torque.
Carpenters' 'thick pencils' may have been used to draw the performance graphs - but they got there or thereabouts, and created an engine that stayed in production for 50 years. Also seen in Dennis fire engines, some military applications, and I believe in some boats. Fantastic bit of design in my view, truly iconic, and an absolute joy to take to bits and put together.
Without a decent radiator, or even ANY radiator, must have been for the drag strip only in a bike context I reckon. Hard enopugh to keep them cool in cars even with best part of 30 pints of water aboard sometimes!
They used also to say the Vanwall was 4 Manx Nortons in a line . . .
