Walterjn American LeMans for me....
I like that and IMSA Sports Cars the best but I also like Formula 1 and Indycars. My favorite racing that I ever saw was back in the days of CANAM. The cars looked like IMSA prototypes but they basically had no regulations. It was pretty much
"Run what you brung." I saw them race in northern Minnesota at Donnybrooke (now called Brainerd International).
I got to see many of the all time greats race there. People like Mark Donohue, Jackie Stewart, Bruce McLaren, Dan Gurney and Peter Revson. My first trip to that race resulted in crashing my 1969 Mustang Mach 1... and it was still worth it.