What is the limit to the MBC entertainment program "Infinite Challenge"? The MBC entertainment program "Infinite Challenge" ranked top for eleven consecutive weeks this week, according to the national viewing rate survey company Nielsen Korea. The racing special episode of the entertainment program "Infinite Challenge" recorded 10.2% national viewing rate, which was higher than that of last weekend's episode. On this day's episode, the Infinite Challenge members attended the Korean Speed Festival (KSF) car race, but did not succeed in completing the race, due to unfortunate collision accidents. The MBC entertainment programs "Infinite Challenge" members have been practicing for a relay car race at the Korea Speed Festival (KSF) which took place on July 6, 2014.