FIA-recognized cars categorizations in motorsport

I am interested to know how the cars in motor racing were categorized and classed by FIA during the history of motorsport. I mean following categorizations:

Since 1982 we had:

Group N - Serial Touring Cars
Group A - Touring Cars
Group B - Special Touring Cars and GTs
Group C - Sports Prototypes
Group D - International Formula
Group E - National and Single-Make Formula

Later a complete chaos appeared with Groups H, CN, C3 then F, M, ST, GT1, GT2, DTM and every national union seems to have their own rule sets. But I am more interested in earlier designations. I can write down what I know with a hope anybody could fill the rest and correct it:

Before 1982 there were following milestones:

1976:
====
Category A:
Group 1 - Serial Touring Cars
Group 2 - Special Touring Cars
Group 3 - Serial Grand Touring Cars
Group 4 - Special Grand Touring Cars
Group 5 - Special Production cars based on cars homologated in Groups 1÷4 (Silhouettes)
Category B:
Group 6 - Sports Cars
Group 7 - International Formula
Group 8 - National and Single-Make Formula

I am less sure about how it was before but here are pieces I am aware of:

1972:
====
Category A:
Group 1 - Serial Touring Cars
Group 2 - Special Touring Cars
Group 3 - Serial Grand Touring Cars
Group 4 - Special Grand Touring Cars
Category B:
Group 5 - Sports Cars
Group 6 - not sure if it was used but would be for prototypes that now belonged to Group 5
Group 7 - Sports Racing Cars
Category C:
Group 8? - International Formula (Racing Cars)
Group 9 - National and Single-Make Formula

1970:
====
Category A:
Group 1 - Serial Touring Cars
Group 2 - Special Touring Cars
Group 3 - Serial Grand Touring Cars
Group 4 - Special Grand Touring Cars
Category B:
Group 5 - Sports Cars (25 cars built)
Group 6 - Sports Prototypes
Group 7 - Sports Racing Cars
Category C (or B?):
I don't know how Racing Cars were sorted before at all. Probably same as in 1972-75 but were they category B?

1968:
====
Category A:
Group 1 - Serial Touring Cars
Group 2 - Touring Cars
Group 3 - Grand Touring Cars
Group 4 - Production Sports Cars (like Lola T70, Ford GT40) - 50 cars built
Category B:
Group 5 - Special Touring Cars
Group 6 - Sports Prototypes
Group 7 - Sports Racing Cars

Before I know only that Group 7 cars were in fact Group 9/Category C in mid 60s and also following categories from 1955 (not sure when that rule set started and ended):

1955:
====
Group 1 - Serial Touring Cars (???)
Group 2 - Grand Touring
Group 3 - Special Touring Cars
Group 4 - Serial Sports Cars
Group 5 - Racing Sports Cars


I would appreciate if anybody could complete these records according to official FIA regulations. And does still exist any official categorization by FIA these days? I think they never cancelled or updated their 1982 categorization despite groups C and B are no longer raced and many other types of machines supported officially by FIA appeared (ST, WRC, GT, SR1, SR2, LMP to name some).

I'm sure the Group 7 was the class of the Can-Am cars, sometime named "two-seat cars", or something similar, in the 60s and 70s. Probably also the small prototypes of the "European 2-litre Championship" at the beginning of the 70s were under Gr. 7 rules. And also some European Mountain Championship cars in that years.

For example:
Ferrari 512S, Porsche 917, Ford GT40 etc. were in Gr. 5
Matra MS650, Alfa Romeo 33.3, Mirage M6-Ford etc. were in Gr. 6
McLaren M8A-Chevrolet, Porsche 917-10, UOP-Shadow etc were in Gr. 7

Nanni, you are correct, I also recall that Can-Am type cars were Group 9 in about 1965. That's well known fact but that fits just 1970-1971 period as I wrote above. Before 1970 Ford GT40 was Group 4 and after 1971 Alfa Romeo and Matra were Group 5.

Nobody had any new information? Maybe number of cars built for homologation would be also intersting (I put it only at 1969-1970 Sports Cars while it is obvious there is no limit for any Prototypes, Sports Racers or Racing Cars).

1966 was the crucial change year for Gp1 (5000 in 12 months instead of 1000) Gp2 remained 1000 and Gp3 was 500 (previously 50?).

http://forums.autosp...ighlight=groups

Hello Martin - this link should give you some more answers...

Best regards
Jesper

A definitive list by Group would still be a lot less than the full story, since there were often very significant changes within the definitions every few years. It is not possible to say what modifications were permitted in a particular Group, only what were allowed in the Group at a particular year. That still applies - Group N, for example, has changed out of all recognition, now being far closer to what GpA was when introduced in 1982. Group 2 became much less restrictive until it was tightened up for 1978 to such an extent that top level rallying found loopholes to re-homologate the earlier Gp2 cars as Gp4.

Thanks, Jesper. It seems that also the old thread didn't turn more into the history, i.e. 1950s and early to mid 60s. Is for the 'known' years I have still doubts about using Group 6 in 1972-75 period. All former Group 6 cars ran now as Group 5 and I am not aware of any series run to so called Group 6 cars in that period.
That overview also doesn't mention that in 1976 Group 7 was cancelled and instead Group 8 and Group 9 became Group 7 and Group 8 respectively. I am pretty confident about that.
But generally I am more interested in older years as much knowledge goes to zero:-).

RS2000, you are correct that rules used to change but nevertheless I am interested in what groups we used any particular year. As far as I know a big change for Group 2 cars happened after 1975 season, at least in ETCC. I am not aware of 1978 changes....