I am not a voice teacher, however I do know it is not very often for a voice type to deviate by much. From what you describe, it sounds like you are likely a baritono lirico(lyric baritone) or tenore robusto(dramatic tenor).
One way you may determine your passaggi(every singer has two) is to sing one note at a time, first playing the note on a piano, then singing it. You move up the scale chromatically until you find particular notes within your range. These notes are the primo and secondo passaggio.
This is how they are characterized.
When... untrained male singers approach the [end] of the comfortable speech range, they reach a point in the ascending scale where they often involuntarily raise the chin... the corresponding pitch is the first passaggio.
As the untrained singer continues to ascend... the untrained voice will either break off or resort to a sudden falsetto.
I think you may be a tenore robusto because of your lower range. However none of us have actually heard you sing a scale. Therefor, we cant give a definitive answer as too what your voice type is.
- Personal experience
- 7 years of general music lessons
- The book "The Structure of Singing" by Richard Miller