Fellas, my question is this...Is this a vent or a drain? If it is a vent, then this is fine, drainage on the other hand, Jerry hit it on the head. Steve also mentioned cutting in a T, that too is fine and the connection can be done through either a no hub or fernco fitting. Hence the transition from CI to ABS or CI/ABS to PVC.
Big thing is it should be graded to the drain.

Again, Vent or Drain? I'm not sure it was determined from the original post.

Pat