IMSA Prototype Challenge USA 2017: Road Atlanta IMSA Prototype Challenge by Mazda - October 5, 2017October 6, 2017 Coverage of the final rounds of the IMSA Prototype Challenge USA by Mazda, from Road Atlanta. Race 1: http://audio.rpix.org.uk/2017/races/2017_ipcm_plm_r1.mp3 Race 2: http://audio.rpix.org.uk/2017/races/2017_ipcm_plm_r2.mp3
