Nothing to do with formula cars... but interesting none the less to us old timers.
I just finished Harry Hurst's new book "12 Hours of Sebring 1970". Maybe it was just special to me because by 1970 it was already my 7th Sebring and I was pretty into the whole sportscar racing deal by then. I'd walk around the whole viewing area at least twice, once in the day and once at night to see every car going through every turn. I was glued to the fences for the whole 12 hours. Then as soon as the checker flew, we would storm the pits to see glimses of our heros.
Pretty amazing to average 127 mph for 12 hours on Sebring's rough as hell runways, at night, in traffic that may be going half your speed... 35 years ago.
http://www.glorydaysofracing.com