A monk can spend 2 Ki points to heal his Monk level in hit points. May a monk spend 4 Ki points(or more) to heal twice(or more) his Monk level in hit points in the same Standard action?
Based on the RAW, no. The ability does not say "he may heal a number of hit points of damage equal to his monk level for every 2 points from his ki pool he spends." Rather, it limits this to 2.