Clark qualified on pole at a record-breaking 160mph, and simply dominated the race – he led 190 out of 200 laps.
“Jimmy took two laps to settle, then he was gone,” Clark’s then-mechanic Dave Lazenby told Motor Sport.
The 39 design meant that Clark was able to make one less fuel stop than the rest of the field: “Everyone else was shell-shocked by it,” added fellow Lotus old-timer Graham Clode.
AJ Foyt’s transmission failure halfway through meant no one else could hold a light to Clark, but the starting grid had already indicated the times were changing: four of the top five starters were in Lotus cars, nine out out of the top ten used Ford power units and two-thirds of the field now sat in front of their roaring engines, rather than behind.
1966 – Graham Hill
Having only once previously tried – and failed – to qualifying for the Indy 500 in 1963, Graham Hill summed up the mood with perfect British understatement following his ’66 one-off victory: “I’m a bit surprised to have won.”