1960 was the last year of the 2.5 litre F1 formula and the Championship was won by Jack Brabham driving a car with the engine behind the driver.
The 1960 formula 2 was 1.5 litres for which Ferrari developed a V-6 engine.
When the 1961 Formula One season was rule changed down to 1.5 litre it was Ferrari who was ready and easily took the World Championship.
1962 was expected to be more competative - see the years intro:
When the 1966 Formula One season was rule changed up to 1.5 litre it was a repeat of '61 nobody was ready and Brabham took the World Championship by chosing a simple engine that lacked power but was reliable.
1967 was expected to be more competative - see the years intro:
a year explained
A review of the 1969 F1 Championship