We just ran the Enduracers Mod sp1 1.1 at potrero de los funes, and wow, what an awesome track for these cars ... here are the results if anyone is curious about lap times at this track.
http://cmsracing.com/storage/CMS_ES_WD_2011/S2/replays_results/s2_potrero_070311/results/index.html
you can get the track here.
http://www.virtualr.net/potrero-de-los-funes-circuit-1-1-released/