Your chart is for the Amur 'family', which Global Security shows as project 1650 on the table here -
http://www.globalsecurity.org/military/world/russia/ship.htm
It is my understanding, perhaps incorrectly, that the St. Petersburg is a project 677, or Lada class boat on the Global Security chart linked immediately above. (See information to that effect here:
http://www.hazegray.org/worldnav/russia/submar.htm )
I note that the particulars given by HazeGray don't match exactly with any of the boats on the Global Security list for the Amur boats. Of course, one or both of the sources could be wrong, or it really could be two different designs.
