I was looking at Wiki for info on old GPs and noticed that all the cars were given even numbers. Why were no odd numbers used, when did it change to the current system?
odds were issued at Britain.
Evens only at Monaco, the 2nd race of the season.
Odds were in use at the 3rd race, USA
The next two races, back in Europe, Switzerland and Belgium, used evens only… seems to be the fashion in Europe (but not UK )
The current F1 numbering system, where numbers are assigned per the previous years’ constructor standings, has “only” been in use since 1996. 1974 was the first year in which cars were assigned the same number all year long.