I just digged deep into this ‘tyres in F1′-topic recently, mainly to find out how the tyre availability, rules and strategies panned out in the past.
I read a bunch of things, like how Michelin got into F1 in 1977 and its effect (in the book ‘Alpine and Renault’), re-read a fair share of Grand Prix flashbacks here, etc.
What I found out is that obviously in the early days purposeful tyre changes and refuelling were not commonplace, so drivers only changed tyres, if they faced with a puncture or unanticipatedly high tyre wear. I’m fairly sure the year before Michelin really took off, i. e. 1977, Goodyear – as a monopol – provided ‘standard tyres’ for all to use – read about this in a brilliant Alastair Caldwell (formerly of McLaren staff) column on his website, called ’1977 Changing Tyres.’
Then came Michelin and the advent of qualifying tyres, mentioned repeatedly in various sources from 1978, 1979 and 1980.
However, we also know sometimes drivers had the option to choose from a softer and a harder compound for the races as well. Not always though, e. g. Keith wrote in the 1987 British GP flashback that there was only one type of race tyre available for that race and many more around that time. However, it still became obligatory by 1997 and even earlier for the manufacturer to provide two different compounds; I read there were compunds A, B, C and D, a bit like nowadays, but they would move around a bit from race to race, not just in terms of allocation, but in compound modification as well, and the whole system was not as transparent as it is today. Confusingly, I could just as well assume that in the early days (well, around 1980), the softer tyre was actually the qualifying tyre and the super-sticky one-lap Q-compounds came to being a bit later, but no later than 1982, and so drivers really had just one race tyre compound available. Contradicting some of this, a Detroit race in around 1985 was won by Rosberg sticking to the softer tyre for the race and the harder for qualifying, without a mention on qualifying tyres – this was from the official website of the Detroit race (now of IndyCar, of course).
After a long introduction my question is this: does the assuption in the penultimate sentence stand, or there were distinctive softs, hards and qualifying tyres pretty much from 1977-78 onwards (with the rare, or not so rare occasions, when the teams had only the race tyre and the qualifying tyre available)?
Thanks in advance for any more info on this topic.