full throttle vs hell-bent for leather

full throttle

adv

  • All out; at maximum speed, effort, or risk. 

noun

  • A maximum setting on an engine or motor control. 

  • A maximum level of speed, effort, or risk. 

hell-bent for leather

adv

  • Synonym of hell-for-leather (“very fast”) 

  • determinedly recklessly, in a manner that lacks restraint. 

  • Synonym of hell-bent (“(recklessly) determined”) 

How often have the words full throttle and hell-bent for leather occurred in a corpus of books? (source: Google Ngram Viewer )