tourer vs touring car

tourer

noun
  • A touring bicycle. 

touring car

noun
  • A large open car seating four or more people and having a folding top. An automobile designed for touring; specifically, a roomy car, not a limousine. 

  • A type of race car based on a modified production car, that is a sedan or saloon car. 

How often have the words tourer and touring car occurred in a corpus of books? (source: Google Ngram Viewer )