It looks to me like an Argentine BCI. I could be wrong, but the Argentine's tend to be darker with lots of speckling. If that's the case, this appears to be a young snake - these guys also tend to get fairly large....
Either way, it's a very nice pretty snake! Congrats!
She's beautiful is what she is! She reminds me of a really contrasty Central American (Nicaraguan) boa, but that's mostly because of the head pattern. A body pattern shot could be helpful, I'm sure some boa experts (unlike me lol) will chime in soon though.
1.0 Normal - Maynard
1.0 POG - Victor
0.1 YB - Diana