You would combine two 1/8" bends.
A long sweep 90 is equivalent, the same as an 1/8 bend and street 1/8 bend put together.
I'm looking at the CA Plumbing code and it says:
"Changes in direction of drainage piping shall be made by appropriate use of approved fittings and shall be of the angles presented by a one-sixteenth (1/16) bend, one-eighth (1/8) bend, or one-sixth (1/6) bend, or other approved fittings of equivalent sweep."
I can't figure out why a right angle is not included in this list. Are there no 90 degree bends in drain pipes? Thanks for any help.
Of course there are, but the actual application determines WHICH 90 can be used.