Since almost the first day I started reading this forum almost 4 years ago,  I was told that some day, in the far distant future, my gold problems would suddenly end when I was finally able to run the LeMans "10 lappers".   The old timers never said exactly where these events were and, after completing almost 5300 events, I was beginning to wonder if they still existed.  Maybe the Monkees had deleted them. 

Which brings us to the "Endurance Legends" series. The series is  unique in several respects. 
(1) It uses six cars organized in two sets.  The three "2014" cars are only used in the 1st 5 tiers after which you have to have one of the "2015" cars to proceed. 
(2) All the events are cup races and they are organized so that within each tier the 3 races are variations of the same track.  Tier 1: Red Bull, Tier 2: Porsche, Tier 3: Nurburgring, Tier 4: Suzuka, Tier 5: Le Mans.  
(3) Almost all the events are longer than you find in other series.  For example, the tier 4 races are 6, 8, and 10 laps. All three LeMans events are 10 laps.
(4) Most importantly, the series remains locked until you have completed at least half of the Ferrari F14 series, which explains why I only just found the "10 lappers".   

Finally have an alternative to the 4 lap LeMans event in the Master-level "Classic Ferrari Showdown" series.
 
[Edit]   Porsche 919 (PR 94)  vs F40 (PR 58).   919: Total time 31:48. Best Lap 3:07.   F40: On a few occaisions was able to do a 3:45.