Your favourite racing series and seasons.

So many but if I had to pick in the main categories of motorsport:

USAC champcars 1973 or 74 but also CART in the 90s so many good ones.
Grand National Nascar 1970
TransAm 1970
Formula 1, tough call but probably 1976
Group C seasons, 1990 was great with many different cars
Sportscars, probably 1997-98 FIA GT even if it was mostly a Mercedes show but so many nice entries
Single make BMW M1 procar

For me... tough call.

Gotta agree with Alberto on the NASCAR Grand National 1970 Season, however.
Add to that... Well, quite obviously, despite the two driver deaths and the political drama, the 1982 Formula One season.
1988 British Rallycross Championship comes to mind, too.
2000 DTM season
anything else? oof....not sure.

Been watching through most of the German touring car scene of the 1990's lately. DTM 1990-1992 was epic, albeit very political. STW was awesome too for all it's lifetime.

For me there is a slightly smaller sample-size, since I'm on the younger side of sim-racing (I suppose, being born in the ninetees), but here goes:

Touring Cars:
There are two sides to this, one is the Australian series, especially the Group A days of the 80's and the mid- to late-ninetees V8's which produced some stonking races and great title fights, as well as some very memorable Bathurst events.
The other one is 90's BTCC. While the Gr. A days of the BTCC lends to some great driving in the virtual world, few things beats the titanic fights that occured in the 90's in the Super Tourers. It also helped that Richard Rydell, the swedish flowerist, was a part of the series back then.

F1:
For me, F1 will always be at its best when the drivers at the top were named Schumacher, Häkkinen, Coulthard, Frentzen, Hill, Irvine etc. Those were the days I remember, with a fond memory at that.

CART:
The years that Kenny Bräck was in there, turning heads and proving that Sweeds could also make it in America, although in different ways than what they themselves thought when they went over in the 1800's...


Few other races were ever broadcast on channels that I could watch and therefore few other series made an impression on me when I was younger. In later years I've found USCC to provide some decent action from time to time, but I can't say that I've been following it at all like I've followed and watched the afformentioned series.

1993 CART season, what a year with Nigel Mansell the current F1 world champion, Mario Andretti, Emerson Fittipaldi, Nelson Piquet (at Indy) all F1 world champions. Lots of other ex F1 drivers plus the best of the US drivers. A Penske and Lola manufacturer battle, the Rahal-Hogan RH-001 disaster, and Ford and Chevy engines along with Buick at Indy.
en.wikipedia.org/wiki/1993_PPG_Indy_Car_World_Series
I hope that we can get to race the 1993 season here at some point.

Group C 82-92 (virtua_LM Le Mans 83 complete grid) 1989 best season car on grid
WTCC 1987

Ahhh, good call on Japanese Series, AND F Atlantic!!
Forgot about those

CART 96-99, F1 97