SFTP does not have any notion of binary vs. text/ASCII. Nor does it have a notion of Content-Type.
SFTP is binary. It simply provides file access, file transfer and file management. The content of the files is of no interest to SFTP. It does none of the things FTP does to destroy, er, “help” text files and EOL termination. 
#Integration-Server-and-ESB#webMethods